1846, "medical treatment of disease," from Modern Latin therapia, from Greek therapeia "curing, healing," from therapeuein "to cure, treat medically," literally "attend, do service, take care of;" related to therapon "servant, attendant."
therapy ther·a·py (thěr'ə-pē)
n.
The treatment of illness or disability.
Psychotherapy.
A healing power or quality.
Treatment intended to cure or alleviate an illness or injury, whether physical or mental.