dispossess v.

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).

late 14c., possessen, "to hold, occupy, inhabit" (without regard to ownership), a back formation from possession and in part from Old French possesser "to have and hold, take, be in possession of" (mid-13c.), from Latin possessus, past participle of possidere "to have and hold, hold in one's control, be master of, own," probably a compound of potis "having power, powerful, able" (from PIE root *poti- "powerful; lord") + sedere, from PIE root *sed- (1) "to sit."

According to Buck, Latin possidere was a legal term first used in connection with real estate. The meaning "to hold as property" in English is recorded from c. 1500. That of "to seize, take possession of" is from 1520s; the demonic sense of "have complete power or mastery over, control" is recorded from 1530s (implied in possessed); the weakened sense of "fascinate, enthrall, affect or influence intensely" is by 1590s. Related: Possessed; possessing. The other usual Latin verb for "to possess," tenere, originally was "to hold," then "occupy, possess" (see tenet).

"act of putting out of possession," 1570s, noun of action from dispossess.