anticlimax n.

word-forming element of Greek origin meaning "against, opposed to, opposite of, instead," shortened to ant- before vowels and -h-, from Old French anti- and directly from Latin anti-, from Greek anti (prep.) "over, against, opposite; instead, in the place of; as good as; at the price of; for the sake of; compared with; in opposition to; in return; counter-," from PIE *anti "against," also "in front of, before" (from root *ant- "front, forehead," with derivatives meaning "in front of, before"), which became anti- in Italian (hence antipasto) and French.

It is cognate with Sanskrit anti "over, against," and Old English and- (the first element in answer). A common compounding element in Greek, in some combinations it became anth- for euphonic reasons. It appears in some words in Middle English but was not commonly used in English word formations until modern times. In a few English words (anticipate, antique) it represents Latin ante.

In noun compounds where it has the sense of "opposed to, opposite" (Antichrist, anti-communist) the accent remains on the anti-; in adjectives where it retains its old prepositional sense "against, opposed to," the accent remains on the other element (anti-Christian, anti-slavery).

1580s, in the rhetorical sense ("a chain of reasoning in graduating steps from weaker to stronger"), from Late Latin climax (genitive climacis), from Greek klimax "propositions rising in effectiveness," literally "ladder," from suffixed form of PIE root *klei- "to lean."

Originally in rhetoric an arrangement of successive clauses so that the last important word of one is repeated as the first important word of the next, as in Romans v.3-5: "... but we glory in tribulations also: knowing that tribulation worketh patience; and patience, experience; and experience, hope: And hope maketh not ashamed ...." Compare anadiplosis. From the rhetorical meaning, the word evolved through "series of steps by which a goal is achieved," to "escalating steps," to (1789) "high point of intensity or development," a usage credited by the OED to "popular ignorance."

The meaning "sexual orgasm" is recorded by 1880 (also in terms such as climax of orgasm), and is said to have been promoted from c. 1900 by birth-control pioneer Marie Stopes (1880-1958) and others as a more accessible word than orgasm (n.).

also anti-climactic, "of the nature of an anticlimax," 1831; see anticlimax + -ic.