• ensure •
Pronunciation: en-shur • Hear it!Part of Speech: Verb, transitive
Meaning: To make sure, secure.
Notes: Assure, ensure, and insure all mean "to make sure or certain". Only assure is used with reference to a person in the sense of "to relieve of worry": "The president assured the ambassador of his job." Ensure and insure are interchangeable among British English speakers, but in American parlance only insure is used in the commercial sense of "to guarantee persons or property against risk". The British term for life insurance is (life) assurance.
In Play: Here is a sentence that exemplifies for US readers the two verbs that aren't ensure: "Her parents assured Helen Highwater that they had insured their car sufficiently for her to drive it without worry." Here is a sentence that exemplifies ensure: "Helen had to limit the time her kids spent watching TV to ensure they did their homework."
Word History: Today's Good Word in Middle English was ensuren, from Anglo-Norman enseurer, comprising Old French en-, a causative prefix, + seur "safe, secure", a variant of French sur. Sur was a reduction of Latin securus "carefree, careless", made up of se- "without" + cura "care". The first component of this word, Latin se(d)-, comes from PIE s(w)e- "self, on one's own, alone", visible in such Latinate borrowings as segregate, separate, and sever. Cura comes from ancient Latin coisa, the origins of which are unknown. (Let us now ensure that Debby Moggio receives the gratitude she deserves for recommending today's triply ambiguous Good Word.)
