lapsedEnglishOxford American Thesauruslapsed adjective 1 a lapsed Catholic: non-practicing, lacking faith, backsliding, recidivist, apostate; formal quondam. ▷antonyms practicing, devout. 2 a lapsed season ticket: expired, void, invalid, run out, out of date, terminated, discontinued, unrenewed. ▷antonyms current, valid.