n. (pl. -ies) 1 infinite or unending (esp. future) time. 2 Theol. endless life after death. 3 the state of being eternal. 4 colloq. (often prec. by an) a very long time. 5 (in pl.) eternal truths. eternity ring a finger-ring set with gems all round, usu. given as a token of lasting affection.
[ ME f. OF eternité f. L aeternitas -tatis f. aeternus: see ETERNAL ]