1. relapse into bad ways or error:"converted vegetarians backslide to T-bones"Similarrelapselapseregressretrogressrevert to one's bad habitsweakenlose one's resolvegive in to temptationgo astrayleave the straight and narrowgo down the primrose pathdegeneratedeteriorateslipslidefall offrevert to a former stateregressretrogressinformal:go downhillgo to potgo to the dogsrare:recidivateOppositepersevereprogress