incorrect adj.

word-forming element meaning "not, opposite of, without" (also im-, il-, ir- by assimilation of -n- with following consonant, a tendency which began in later Latin), from Latin in- "not," cognate with Greek an-, Old English un-, all from PIE root *ne- "not."

In Old French and Middle English often en-, but most of these forms have not survived in Modern English, and the few that do (enemy, for instance) no longer are felt as negative. The rule of thumb in English has been to use in- with obviously Latin elements, un- with native or nativized ones.

mid-14c., "to set (someone) right by punishing for a fault or error, to discipline;" late 14c., of texts, "to bring into accordance with a standard or original," from Latin correctus, past participle of corrigere "to put straight, attempt to make (a crooked thing) straight, reduce to order, set right;" in transferred use, "to reform, amend," especially of speech or writing, from assimilated form of com-, here perhaps an intensive prefix (see com-), + regere "to lead straight, rule" (from PIE root *reg- "move in a straight line," with derivatives meaning "to direct in a straight line," thus "to lead, rule").

Meaning "to remove or counteract the operation of" is from late 14c. Related: Corrected; correcting.