WARNER, J.
Plaintiff-appellant was at one time employed as a teacher in the public schools of the city of Portland, Oregon, by the directors of School District No. 1 of Multnomah county, the defendant-respondent. She brings this action to recover damages claimed to have been sustained by reason of defendant’s refusal to [76]*76recognize her alleged right to continued employment as a “permanent” teacher. From a judgment of involuntary nonsuit, plaintiff appeals.
Beginning in 1938, and for many years following, plaintiff taught millinery in Girls’ Polytechnic High School; but during the school year 1949-50, and thereafter, the district refused to employ her except on a part-time basis.
Plaintiff represents that, having previously taught full time for three successive school years as a teacher regularly appointed and employed with an annual salary, she thereby acquired a permanent status under the Teachers’ Tenure Law (§§ 111-2301—111-2320, OCLA) and, having that status, contends that the district is obligated to continue to employ her. The plaintiff has arbitrarily selected the history of her employment during the school years of 1933-44,1944-45 and 1945-46 upon which to predicate and demonstrate the righteousness of her claim.
The district controverts these contentions, alleging that during the foregoing school years, her employment was only as an “assigned substitute” and, relying on § 111-2304, OCLA, asserts that by virtue of that circumstance she was specifically excepted from the benefieient provisions of the tenure law.
This appeal calls for the resolution of three principal questions: First, Do all teachers of the district (other than substitutes) have to pass through a probationary status before attaining a “permanent” classification, or can the board under the provisions of § 111-2304 regularly appoint and employ some of them without subjecting them to the tests involved in the elevation from probationary to permanent rank? Second, Is a teacher who is appointed and regularly [77]*77employed to fill a position not temporarily vacated by the absence of another regularly retained, denied the benefit of tenure status because in her contracts for such service she is described as an “assigned substitute”? Third, If the teacher’s employment was initially within the power of the district and evidenced by contracts not executed with all the statutory formalities, can the district thereafter ratify them?
Before examining the Teachers’ Tenure Law in the light of the divergent positions of the respective parties, it will not be amiss to note that this law has as its foundation the all important public policy of giving further protection to the educational system of our state, rather than the granting of special privileges to teachers as a class or as individuals. Its broad objective is to maintain stability in teaching staffs and to avoid the evils of a fluctuating personnel so frequently incident to manifestations of prejudice, favoritism or arrogance on the part of school administrators. It therefore follows that the act should receive a liberal construction to effect its general plan as an act designed to promote the public interest. State v. Stout, 206 Ind 58, 187 NE 267, 269; McSherry v. City of St. Paul, 202 Minn 102, 277 NW 541, 546.
We look first to § 111-2304, OCLA, since it is the section of the tenure law wherein we find the basic requirements prerequisite to the attainment .of permanent or “tenure” status. It reads:
“The words ‘teacher’ or ‘teachers,’ when used in this act, shall mean and include all supervisors, principals, vice principals, directors of departments and/or instructors now employed, or who hereafter may be employed, by any such school district. ‘Permanent’ teacher or teachers shall mean and include all teachers who have been regularly ap[78]*78pointed and employed by any such school district for not less than three successive school years, of who may hereafter be placed upon the permanent list by resolutions of the school board as hereinafter provided. ‘Probationary’ teacher or teachers shall mean and include all teachers, other than substitute teachers, regularly appointed and employed by any such school board during a probationary period of three successive school years, and until placed upon the permanent list as provided in section 111-2307.” (Italics ours.)
Section 111-2307, OCLA, referred to in § 111-2304, as amended by ch 137, Oregon Laws 1945, provides:
“Probationary teachers who have been employed in the schools in any such district or districts as regularly appointed teachers for not less than three successive annual terms, if retained, shall be placed by the board of directors upon the list of permanently employed teachers; * * * provided further, that no probationary teacher shall be placed upon such permanently employed list until the board upon consideration of records and ratings, to be regularly and periodically made to the board, is satisfied as to qualifications and adopts a resolution transferring such teacher from the probationary list to the permanently employed list.”
Plaintiff is in no wise challenged by charges of inefficiency, unbecoming or other conduct which might warrant a dismissal under the provisions of § 111-2311, OCLA. It was stipulated that she was employed on a “substantially full-time basis” during the three school years which are made the basis of her claim for tenure and that during those years she was not tahing the place of a regular teacher absent on leave.
We have deliberately underscored the word “or” in our quotation from § 111-2304, OCLA, in order to focus attention upon the prime point of disagreement [79]*79between the parties. Plaintiff contends that the word should be read literally with its normal disjunctive connotation. The defendant district, on the other hand, argues that it should be given a conjunctive import by reading it as if it were the word “and”.
If we read the word “or” literally, then it becomes evident that permanent status is acquired by a teacher in one of two alternative ways. However, if we are compelled to give the word “ or ” the meaning of£ £ and ’ ’, then a teaching record of three successive years does not ripen into permanent status until the school board adopts a resolution as provided in § 111-2307 of the tenure act. This construction urged upon us by the defendant district is tantamount to saying that all teachers initially and regularly employed by the district must be first employed as “probationary” teachers who can never graduate from their initial probationary standing to permanent status until they have first served the required three successive years and won the board’s accolade in the manner provided by § 111-2307, OCLA.
Courts should exercise circumspection to avoid any effort to amefid statutes. There is no justification for using “or” as meaning “and”, unless the failure to do so would leave a statute meaningless or absurd. It is an inexcusable device of interpretation where there is no ambiguity to be resolved. Generally, the words “and” and “or”, as used in statutes, are not interchangeable, being strictly of a conjunctive or disjunctive nature, respectively; and their ordinary meaning will be followed if it does not render the sense of the statute dubious or circumvent the legislative intent, or unless the act itself furnishes cogent proof of the legislative error. State v. Kelly, 218 Minn 247, 15 NW2d 554, 162 ALR 477, 490; Tedars v. Savannah [80]*80River Veneer Co., 202 SC 363, 25 SE2d 235, 147 ALR 914, 919; 50 Am Jur, Statutes, 268, § 282; 82 CJS, Statutes, 672, § 335.
Taking the tenure law by its four corners, we do not find § 111-2304, OCLA, rendered ambiguous,'meaningless or absurd by the legislative use of the controverted word “or” in its usual meaning and disjunctive employment and cannot accept defendant’s suggestion that we substitute “and” in place thereof and thereby give a conjunctive character to the phrase which follows ; nor do we think the foregoing conclusion is violative of the legislative intent. Indeed, if we accept defendant’s premise, it is plain to us that we must also conclude that all teachers who are regularly appointed and employed by a school district must be initially employed on a probationary basis (except, of course, substitute teachers) and that all, after three years of such service, must thereafter be subjected to board review of their records required by § 111-2307 before they can successfully attain permanent status.
We do not so read the tenure law. We find nothing therein which inhibits a school district from regularly employing any teacher without first subjecting such instructor to a probationary period. The word “teachers”, as used in the act, comprehends the whole gamut of instructors from the elementary school to those presiding over high school classes. Within the statutory definition of the word “teacher” is also included high ranking administrative employees: supervisors, principals, vice-principals and directors. § 111-2304, OCLA. Offices with such administrative responsibility are ordinarily assigned only to those who have proved their worth through long prior experience. To hold, as defendant would have us do, that all “teachers” must first submit to three years of probationary test[81]*81ing would deny to the 'school board the valuable opportunity to choose from many experienced men and women with well established reputations in their profession but who might hesitate to accept appointment because of their unwillingness to subject themselves to the vicissitudes and uncertainties of probationary employment. § 111-2306, OCLA.
The earlier counterpart of § 111-2306, (as it was originally enacted in 1935) and its immediate predecessor as legislation treating with the same subject matter, was § 35-2603, Oregon Code 1930, a part of the tenure law enacted in 1913. Section 35-2603 expressly directed that “The teachers employed in any such district or districts during their first two years of service shall be classed as probationary teachers.” This mandate of the 1913 tenure act would give cogent substance to defendant’s argument if it or its equivalent could be found in the later tenure law of 1935, which supplanted in its entirety the act of 1913.
The inclusion of the controverted provision of § 111-2304, OCLA, as presently drawn, coupled with the deletion of the inflexible mandatory direction compelling probationary employment as originally written into § 35-2603, is in our opinion clear and conclusive evidence of the legislative intent to vest district school boards with powers of a discretionary latitude whereby the services of some teachers might be retained without subjecting them to the incident uncertainties of probationary status and thereby enlarging the field from which teachers of proven ability and experience can be chosen.
With no statutory mandate dictating that all teachers employed by the district must be placed on a probationary basis for three years, it follows that a school board can create two alternative Mnds of “regu[82]*82lar teacher” employment: (1) Those who are not subjected to probationary status and (2) those who are. All thus regularly employed must, of course, serve at least three successive school years before attaining eligibility for permanent tenure; but only those who are on probationary status are subjected to the district board’s favorable resolutions before their permanent status is finally determined. To hold otherwise would be to circumvent what appears to us as the legislative intent.
In order to enjoy permanent status under the tenure law, it is unnecessary for plaintiff to prove that she was first placed on probationary status and thereafter elevated to permanent status pursuant to a resolution provided for by § 111-2307 OCLA, if she can show that she was a regularly employed teacher for three successive school years and not engaged during that time as a substitute temporarily employed during the absence of other regularly employed instructors.
Notwithstanding the foregoing conclusion, we still have before us the necessity of disposing of the second question propounded by this appeal, i.e., deciding whether plaintiff was a regularly employed teacher in contradistinction to employment as a probationary teacher or as a substitute.
No contention is made by the district that she was on a probationary status during the school years in question. To the contrary, defendant insists that she was only a substitute teacher during that time or, as it describes her, an “assigned substitute”.
Sections 111-2304 and 111-2305, OCLA, respectively incorporate and expand the fundamental thought initially enacted by ch 152, § 3, Oregon Laws 1917, and by ch 37, § 2, Oregon Laws 1913. Concerning the acts of 1913 and 1917 last referred to, this court held in Tag[83]*83gart v. School District No. 1, 96 Or 422, 435, 188 P 908, 1119, that they had no application to substitute teachers; and we now, and for the same reasons there given, so hold with reference to the present Teachers’ Tenure Law of which §§ 111-2304 and 111-2305 are integral parts. It follows, therefore, that if plaintiff was employed as a teaching substitute in the legal or common acceptation of that term, she has no standing here. If, however, plaintiff’s services were rendered as a regularly employed teacher not retained on a probationary basis, then the appellation “substitute” loses its ordinary connotations and does not stand as a bar to such rights as plaintiff is entitled to claim under the tenure law.
It is defendant’s contention that during all the teaching periods here involved, plaintiff’s status was that of an “assigned substitute”, a term not included in the nomenclature of the tenure law. The claim rests upon a like phrase used in the contracts made with plaintiff for the teaching years beginning respectively in 1943, 1944 and 1945.
In the absence of a statutory or judicial definition, the true nature of the employment should be determined by an examination of its characteristic constituent elements and not as defined by a descriptive word or phrase arbitrarily applied. This is particularly true when the descriptive words so used in and of themselves suggest a meaning wholly at variance with the distinctive qualities of that particular service. In short, the test is what the plaintiff did, not what she was called.
At the threshold of this line of argument, the defendant district is confounded with its stipulation to the effect that plaintiff was employed on a substantially full-time basis during these three controlling school [84]*84years and, while so engaged, was not taking the place of a regular teacher absent on leave.
The word “substitute”, although used in the tenure act, is not there defined, nor has this court heretofore had occasion to define it judicially. This omission is not strange, because of its generally accepted and long familiar meaning to all who have ever attended a school. However, we have made reference to persons in that status as being “substitute teachers temporarily employed” and substitute teachers who are “employed to take the place of another teacher for a week or a day”. Taggart v. School District No. 1, supra, at 435. These phrases comport with both the academic and legal acceptation of the word “substitute” as one who takes another’s place in case of the latter’s absence. Schulz v. State Board of Education, 132 NJL 345, 40 A2d 663, 669; Webster’s New International Dictionary (2d ed).
We are told by the respondent district that the words “assigned substitute” are words of administra-tive convenience with no foundation in law and that, as so used by School District No. 1 here, they can mean, among other things, persons ‘‘ substituting in a temporary position for which there is no regular teacher.”
Whether plaintiff was serving in a “regular” or “temporary” position and what constitutes a “regular position” as distinguished from a “temporary position” are matters not before us nor necessary for determination in this decision; but we do note that the test of tenure for teachers under the present law is not made contingent upon the kind of position they are selected to fill, that is, regular or temporary, but rather upon the regularity of their employment, if not probationary, and the successive years of such employment. So far as the tenure act is concerned, teachers’ claims to permanent status cannot be impaired by the [85]*85fact that they are assigned to teach courses which, for administrative convenience, the school board may treat as experimental or temporary courses. Permanent status does not, however, impose upon the district a duty to employ continuously a teacher with that rating when the board determines, in the exercise of good faith, that such employee’s services must be discontinued because of the demands of economy or by reason of a lack of pupils. Funston v. District School Board, Etc., 130 Or 82, 90, 278 P 1075, 63 ALR 1410.
If it should appear to the school board that it should be vested with power to accomplish what it is apparently attempting to do, that is, avoid an overloading of its permanent teacher rolls while speculating on the continuance of a given teaching course, then we submit that it should seek relief from the legislature rather than by arbitrarily attempting to circumvent the tenure law by the employment of phrases designed to cover conditions not expressly excepted from the operation of that law.
We have no occasion to impugn the integrity or good faith of the board in its apparent eagerness to save the district additional expense incident to an overloading of the permanent teacher rolls; but we submit that the device here employed to avoid such a situation, if, in fact, such was its objective, is fraught with grave dangers and can, unless condemned, become a wicked instrumentality in the hands of school officials unfriendly to the tenure law.
Our answer to the second question is that plaintiff during the several school years was not acting as a substitute but in a capacity as regular as any regularly employed teacher and that the use of the words “assigned substitute”, as applied to her, does not work [86]*86to destroy or temper her rights under the tenure act, unless it can be said that she was not “regularly appointed and employed” during her three successive years of service in the sense that it challenges the legal sufficiency of the formalities of her contracts.
The defendant district makes the formality of the execution of plaintiff’s contracts an issue in this matter and thereby injects a challenge to the power of the school district to ratify subsequently a previous contract irregularly executed, notwithstanding that the agreement had the character of one which the district had the power to authorize in advance.
The faets upon which the defendant district depends are substantially as follows: For the school year 1943-44, the board by resolution directed a contract in letter form wherein the teachers to be employed were described as “assigned substitutes”. Plaintiff was mailed such a contract, accompanied by a covering letter setting forth the terms of the employment for a full school year. Both the letter and contract were signed by one of the district’s assistant superintendents—and the contract by the plaintiff. The salary schedules referred to therein were established by a motion recorded in the minutes of the board. Thereafter, plaintiff was paid in accordance with such schedules by warrants signed by the chairman of the board and its school clerk.
Substantially the same procedure was followed for the school years 1944-45 and 1945-46, with the exception that there was no resolution directing the form of contract to be used. Notwithstanding, a form of contract similar to that authorized in 1943 was used in the two subsequent years, and plaintiff received warrants in payment for services in accordance with the salary schedules adopted for those years. They were signed [87]*87by the same officials who had signed the warrants for 1943-44.
Section 111-1041, OCLA, provides for the formalities of making teaching contracts and, insofar as pertinent, reads:
“The board, at a general or special meeting called for that purpose, shall hire teachers and shall make contracts with such teachers which shall specify the wages, number of months to be taught and time employment is to begin, as agreed upon by the parties, and shall file such contracts in the office of the district clerk. * * * When a teacher is hired at a regular meeting and such action is spread upon the minutes, any contract signed afterward in conformity therewith by the chairman, clerk and teacher shall be binding upon all parties. ’ ’
Eatification is claimed by plaintiff by reason of the payment for her service in full for the several years she functioned pursuant to the contracts made. The defendant disclaims power in itself to ratify contracts of the kind made with plaintiff. In support of its position, it relies heavily upon Taggart v. School District No. 1, supra, 96 Or 422 (1920). Contrariwise, the plaintiff asserts that the controlling law is found in Graham v. School District, 33 Or 263, 54 P 185, an opinion written by Mr. Justice Wolverton in 1898.
It is an item of interest, although not of controlling character in the instant matter, to note that if the premise of defendant in this respect is correct, then a host of Portland teachers may discover that they have been serving under invalid contracts with the incident of possible jeopardy to such future claims as they may make under the tenure law, for the particular form of contract employed in the retention of plaintiff’s services was designed by the board’s resolution to be used for all of Portland’s “assigned substitutes”.
[88]*88The pertinent words of Justice Wolverton in the Graham case emphasized by the plaintiff read (33 Or 266):
“But school boards are not unlike the governing boards of other municipalities and corporations, and may by their subsequent acts so adopt or ratify contracts within the scope of their powers, informally entered into or executed, that the districts for which they act will be estopped to deny their validity. * * *”
That part of the Taggart case to which defendant points with a confident assurance was written by Mr. Justice Bennett in response to a petition for rehearing in that matter and states (96 Or 437):
‘ ‘ The brief of this petitioner urges very strenuously that, even if the appointment of the plaintiff was irregular, yet that it was not entirely void, and that it could be and was ratified by the acceptance of plaintiff’s services, and many authorities are cited to support the contention that after she had taught, and the district had accepted her services, she could recover for the same, upon the theory that the contract was ratified by the district. Even if we assume that this is the law, it would not help the plaintiff in this proceeding, for she would still not be a ‘regularly’ appointed teacher [i.e., a substitute]. There are many irregular acts and proceedings which are still valid—or may be made valid—validity is one thing, regularity quite another. The legislature has chosen to make regularity, not validity, the test. ’ ’
What at first appears to be a sharp diversity between these two opinions loses much of its force and effect when we make a critical study of the Taggart case. That case was a proceeding in mandamus designed to compel the restoration of Mrs. Taggart to her position and employment as a teacher in the Portland schools. Her claim was predicated upon the theory [89]*89that her prior service as a teacher entitled her to the protection of the tenure law then in effect and that she was entitled thereto despite the fact that her entire teaching service was as a substitute for a regularly employed teacher who was absent from her position by reason of illness and despite the further fact that Mrs. Taggart’s entire period of employment rested upon an oral contract made between her and the superintendent of schools of that city. This court in that opinion, as we have earlier observed, held that as a teacher substituting in the place of a regularly employed teacher, she was not entitled to the benefits of the tenure law. It is apparent from a reading of that opinion that what the court thereafter said concerning the power of the school board to ratify an irregularly made contract was unnecessary and contributed nothing to the result there reached, for the reason that, had Mrs. Taggart’s employment been evidenced by a contract executed with all the formalities of law, she still would not have been entitled to claim a place on the permanent rolls under the tenure act. It follows, therefore, that the statement in the Taggart case relied upon by the defendant district is dictum and, ipso facto, loses much of its persuasive force, particularly when read with the doctrine of contract ratification laid down in Graham v. School District, supra.
The rule of ratification announced in the Graham ease is well established in its application to the contracts of school districts. 47 Am Jur, Schools, 331, § 50; Hamilton and Mort, The Law and Public Education, 284-85, 330-31; Voorhees, The Law of the Public School System, 127, § 58.
This court has never cited the Taggart case as authority for the proposition advanced by the defendant in the intervening 30 years since its initial pronounce[90]*90ment. To the contrary, since the decision in the Graham ease we have repeatedly recognized the right of ratification of irregularly executed contracts as therein expounded and have many times applied it to irregularly executed contracts made by other public or municipal entities of this state. See Mount v. Welsh et al., 118 Or 568, 587, 247 P 815 (a contract for a post-mortem examination); McKenna v. McHaley, 67 Or 443, 447, 136 P 340 (a county contract for the services of a deputy district attorney); Cunningham v. Umatilla County, 57 Or 517, 519, 112 P 437, 37 LRA NS 1051 (a county contract for detective services); Steiner v. Polk County, 40 Or 124, 125, 66 P 707 (a county contract for professional services).
Bmdall S. Jones and Robert Tj. Weiss, of Portland, argued the cause for appellant.
Grant T. Anderson argued the cause for respondent. On the "brief were King, Miller, Anderson, Nash & Yerke, of Portland.
Assuming that a school board has authority, in the first instance, to .make contracts of the kind challenged on the ground of irregular execution, the public is not thereby deprived of any substantial protection by the board’s subsequent ratification. It is our conclusion that the power of ratification so extensively discussed and properly applied in Graham v. School District, supra, should prevail over what is said as dictum concerning the same subject in Taggart v. School District No. 1, supra, and we so hold.
The order of nonsuit will be reversed and the case remanded for a new trial.