| 释义 |
▪ I. optional, a.|ˈɒpʃənəl|
[f. option n. + -al1.]
1. That is a matter of choice; depending on choice or preference; that may be done or left undone according to one's will or pleasure.
1792D. Stewart Hum. Mind iv. §2 (1802) 173 In the former case the use of words is, in a great measure, optional; whereas, in the latter, it is essentially necessary. 1818Jas. Mill Brit. India II. v. viii. 625 Even this burthen was optional, not compulsory. 1884Law Times Rep. LI. 667/1 It was perfectly optional with the defendants whether they treated the cheques..as their own or not. 1934Language X. 120 Occasionally one finds free variants, that is, non-conditional or optional variants. 1964E. Palmer tr. Martinet's Elem. Gen. Linguistics iii. 68 In the case of the actor who ‘rolls’ his r's on the stage but uses the ‘throaty’ pronunciation elsewhere, we may rather speak of ‘optional’ variants. 1971Good Motoring Sept. 18/2 Rubber mats are standard; carpets are an optional extra at {pstlg}10·88. 1972Berman & Szamosi in Language XLVIII. 313 In the above examples, the phenomenon of ‘optional’ stress placement does not seem to correlate with significant differences in meaning or sense.
2. Leaving something to choice. optional clause, see quot. 1776. optional writ, see quot. 1809.
1765Hist. in Ann. Reg. 90 No bank..can issue notes after the 15th of May 1766, containing optional clauses: but such optional notes as are then in the circle may freely pass from hand to hand during any after period. 1768Blackstone Comm. III. xviii. 274 Original writs are either optional or peremptory. 1776Adam Smith W.N. ii. ii. (1869) I. 327 Inserting into their banknotes..an Optional Clause, by which they [Scotch Banks] promised payment to the bearer, either as soon as the note should be presented, or, in the option of the directors, six months after such presentment, together with the legal interest for the said six months. 1809Tomlins Law Dict. s.v., The præcipe was an optional writ, i.e. it was in the alternative, commanding the defendant to do the thing required, or show the reason wherefore he had not done it. 1930[see artificial a. 3 b]. 1962Gloss. Terms Automatic Data Processing (B.S.I.) 39 Optional stop instruction, an instruction which includes the possibility of stopping the operation of the program immediately before or after the instruction is obeyed, there being some means of permitting or inhibiting this facility as required. 1967Technology Week 23 Jan. 11/1 (Advt.), Input/output is managed independently by one built-in and five optional I/O processors, with up to 160 automatic I/O channels. 1970D. Dodge Hatchetman i. 17 ‘Underwriters..are being tapped for U.S. dollar payoffs under an airtight optional-money clause.’ ‘What's an optional-money clause?’.. ‘Most major insurers in international trade write it... You put a clause in your insurance policy giving you an option to take payment in another money of your choice.’
Hence ˈoptionally adv., in an optional way, at choice.
1846in Worcester.
▪ II. ˈoptional, n. orig. U.S.
[f. the adj.]
An optional subject or course of study; a group of students constituting a class devoted to an optional subject.
1855Songs Biennial Jubilee Class of '57 (Yale Univ.) 3/2 For optionals will come our way. 1857Yale Lit. Mag. XXII. 291 What was never known before, since the establishment of optionals, the number pursuing the study of Hebrew is nine. 1900Dialect Notes II. 47 Optional. 1. An optional course selected by a student in addition to his regular work. 2. A student who elects only optional or special courses. 1930Times Educ. Suppl. 12 Apr. 167/3 The advanced mathematics paper set as an ‘optional’ by London University. 1934Times Lit. Suppl. 8 Mar. 162/2 Optional.—An optional subject of study. One example, of 1857, is given from Yale. For over 40 years at St. Paul's School the word has meant the class studying such a subject—e.g., the Spanish optional. |