means The treatment of a physical, mental, or emotional disorder through psychological, medical, or rehabilitative methods, usually guided by a trained professional.

from From Greek 'therapeia,' meaning 'healing, a curing, a serving or attending to'—rooted in 'therapeuein,' to attend, treat, or wait upon. The same root gives us 'therapist,' literally 'one who attends.' It entered English in the 19th century as medicine grew fond of Greek labels, originally for any kind of remedial treatment before the couch and the talking cure made it about the mind.