v.tr. 1 (often foll. by of) a make (a person) sure; convince (assured him of my sincerity). b tell (a person) confidently (assured him the bus went to Westminster). 2 a make certain of; ensure the happening etc. of (will assure her success). b make safe (against overthrow etc.). 3 insure (esp. a life). 4 (as assured adj.) a guaranteed. b self-confident. rest assured remain confident. assurable adj. assurer n.
[ ME f. OF aserer ult. f. L securus safe, SECURE ]