Other forms: relapsed, relapsing, relapses
A relapse is a return of an illness you had almost beaten. Suffer a relapse, a relapse after treatment, relapse rate.
It means falling back after improvement, which is what makes it demoralising as well as dangerous. In addiction, relapse is understood as part of the usual course of recovery rather than as a failure, and treatment plans expect it. In cancer, relapse and recurrence are used for the same thing. Note relapsing, as in relapsing and remitting, the pattern of some conditions.
1nounrelapseA return of an illness you had almost beaten.
“She seemed to be getting better, but then she suffered a relapse and went back into hospital.”
2verbfallTo fall back into a former state.
“He stopped drinking for six months, then relapsed after losing his job.”
relapse is a falling back.
Latin relabi is re- plus labi, to slip. Lapse, collapse and elapse come from the same slipping, so a relapse is a slipping back.
Latin
relapsus
English, today
relapse
Built from
From Latin relapsus, past participle of relabi (“to slide back, fall back”), from re- (“back”) + labi (“to slip, slide, fall”).
Etymology from Wiktionary, CC BY-SA