dis

Roman underworld god, from Latin Dis, contracted from dives "rich," which is related to divus "divine, god," hence "favored by god." Cf. Pluto and Old Church Slavonic bogatu "rich," from bogu "god."

(assimilated as dif- before -f-, to di- before most voiced consonants), word-forming element meaning 1. "lack of, not" (e.g. dishonest); 2. "do the opposite of" (e.g. disallow); 3. "apart, away" (e.g. discard), from Old French des- or directly from Latin dis- "apart, in a different direction, between," figuratively "not, un-," also "exceedingly, utterly," from PIE *dis- "apart, asunder" (cf. 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."

In classical Latin, dis- paralelled 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 new 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.