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.
early 15c., "version, translation, a form of a literary work;" 1550s, "act of publishing," from French édition or directly from Latin editionem (nominative editio) "a bringing forth, producing," also "a statement, account," from past-participle stem of edere "bring forth, produce," from ex "out" (see ex-) + -dere, combining form of dare "to give" (from PIE root *do- "to give"). "It is awkward to speak of, e.g. 'The second edition of Campbell's edition of Plato's "Theætetus"'; but existing usage affords no satisfactory substitute for this inconvenient mode of expression" [OED].