late 14c., "disgraceful, shameful, without honesty or integrity; unjust, unfair, disposed to deceive or cheat; unmodest, unchaste," from Old French deshoneste (13c., Modern French déshonnête) "dishonorable, horrible, indecent," perhaps from a Medieval Latin or Gallo-Roman compound of Latin dis- "not" (see dis-) + honestus "honorable; deserving honor, respectable," from honos "honor, dignity, office, reputation," which is of unknown origin. The Latin formation was dehonestus. Related: Dishonestly.
word-forming element of Latin origin meaning 1. "lack of, not" (as in dishonest); 2. "opposite of, do the opposite of" (as in disallow); 3. "apart, away" (as in discard), from Old French des- or directly from Latin dis- "apart, asunder, in a different direction, between," figuratively "not, un-," also "exceedingly, utterly." Assimilated as dif- before -f- and to di- before most voiced consonants.
The Latin prefix is from PIE *dis- "apart, asunder" (source also of Old English te-, Old Saxon ti-, Old High German ze-, German zer-). The PIE root is a secondary form of *dwis- and thus is related to Latin bis "twice" (originally *dvis) and to duo, on notion of "two ways, in twain" (hence "apart, asunder").
In classical Latin, dis- paralleled de- and had much the same meaning, but in Late Latin dis- came to be the favored form and this passed into Old French as des-, the form used for compound words formed in Old French, where it increasingly had a privative sense ("not"). In English, many of these words eventually were altered back to dis-, while in French many have been altered back to de-. The usual confusion prevails.
As a living prefix in English, it reverses or negatives what it is affixed to. Sometimes, as in Italian, it is reduced to s- (as in spend, splay, sport, sdain for disdain, and the surnames Spencer and Spence).
"unfair or dishonest account," 1640s, from mis- (1) "bad, wrong" + representation.
early 14c., "dishonest praise, coaxing speech," from Old French flaterie "flattery, cajolery" (Modern French flatterie), from flater "to flatter" (see flatter).
early 13c., "bent, curved, in a bent shape," past-participle adjective from crook (v.). In the figurative sense of "dishonest, false, treacherous, not straight in conduct" is from c. 1200. Related: Crookedly; crookedness.
early 15c., from Old French fraudulent, from Latin fraudulentus "cheating, deceitful, dishonest," from stem of fraus "deceit" (see fraud). Earlier was fraudful (c. 1400). The Old French word was fraudios. Related: Fraudulently.
