pro-choice (adj.)

mid-14c., "that which is choice," from choice (adj.) blended with earlier chois (n.) "action of selecting" (c. 1300); "power of choosing" (early 14c.), "the person or thing chosen" (late 14c.), from Old French chois "one's choice; fact of having a choice" (12c., Modern French choix), from verb choisir "to choose, distinguish, discern; recognize, perceive, see," which is from Frankish or some other Germanic source and related to Old English ceosan "to choose, taste, try" (from PIE root *geus- "to taste; to choose").

Late Old English chis "fastidious, choosy," from or related to ceosan, probably also contributed to the development of choice. Choice replaced Old English cyre "choice, free will," from the same base, probably because the imported word was closer to choose [see note in OED].

"opposed to abortion," attested by 1976, from pro- + life. Used earlier in a more general sense of "enhancing life." Hostile alternative anti-choice is attested by 1978 in Ms. magazine (compare pro-choice).

What hypocrisy to call such anti-humanitarian people 'pro-life.' Call them what they are — antichoice. [Ms., Oct. 8, 1978]

word-forming element meaning "forward, forth, toward the front" (as in proclaim, proceed); "beforehand, in advance" (prohibit, provide); "taking care of" (procure); "in place of, on behalf of" (proconsul, pronoun); from Latin pro (adv., prep.) "on behalf of, in place of, before, for, in exchange for, just as," which also was used as a first element in compounds and had a collateral form por-.

Also in some cases from cognate Greek pro "before, in front of, sooner," which also was used in Greek as a prefix (as in problem). Both the Latin and Greek words are from PIE *pro- (source also of Sanskrit pra- "before, forward, forth;" Gothic faura "before," Old English fore "before, for, on account of," fram "forward, from;" Old Irish roar "enough"), extended form of root *per- (1) "forward," hence "in front of, before, toward, near," etc.

The common modern sense of "in favor of, favoring" (pro-independence, pro-fluoridation, pro-Soviet, etc.) was not in classical Latin and is attested in English from early 19c.