- prevent
- early 15c., "to act in anticipation of," from L. præventus, pp. of prævenire "come before, anticipate, hinder," in L.L. also "to prevent," from præ "before" + venire "to come" (see venue). Originally literal; sense of "anticipate to hinder" was in L., but not recorded in English until 1550s. Preventive in the medical sense is recorded from 1640s.