Main Entry: ¹re·lapse

Pronunciation: \ri-ˈlaps, ˈrē-ˌ\

Function: noun

Etymology: Middle English, from Medieval Latin relapsus, from Latin relabi to slide back, from re- + labi to slide — more at sleep

Date: 15th century

1 : the act or an instance of backsliding, worsening, or subsiding
2 : a recurrence of symptoms of a disease after a period of improvement