unripe adj.

prefix of negation, Old English un-, from Proto-Germanic *un- (source also of Old Saxon, Old Frisian, Old High German, German un-, Gothic un-, Dutch on-), from PIE *n- (source of Sanskrit a-, an- "not," Greek a-, an-, Old Irish an-, Latin in-), combining form of PIE root *ne- "not." Often euphemistic (such as untruth for "lie").

The most prolific of English prefixes, freely and widely used in Old English, where it forms more than 1,000 compounds. It underwent a mass extinction in early Middle English, but emerged with renewed vigor 16c. to form compounds with native and imported words. It disputes with Latin-derived cognate in- (1) the right to form the negation of certain words (indigestable/undigestable, etc.), and though both might be deployed in cooperation to indicate shades of meaning (unfamous/infamous), typically they are not.

It also makes words from phrases (such as uncalled-for, c. 1600; undreamed-of, 1630s; uncome-at-able, 1690s; unputdownable, 1947, of a book; un-in-one-breath-utterable, Ben Jonson; etc., but the habit is not restricted to un-; such as put-up-able-with, 1812). As a prefix in telegramese to replace not and save the cost of a word, it is attested by 1936.

Old English ripe, of grain, fruit, seed, a field, "ready for reaping, mature," of animals used as food, "fit for eating," from West Germanic *ripijaz (source also of Old Saxon ripi, Middle Dutch ripe, Dutch rijp, Old High German rifi, German reif); related to Old English repan "to reap" (see reap).

Usually explained as "fit for reaping," in which case it would have been originally of grains and extended to all fruit. Figurative use by c. 1200. As "full-grown, developed, finished" (a ripe age) by late 14c. The meaning "ready for some action or effect" (as in the time is ripe) is from late 14c. Of lips, the mouth, "round and full, like ripe fruit," by 1580s. Related: Ripely. The proverb soon ripe, soon rotten is attested by 1540s.