This suffix originates from two Greek root terms [ectos], meaning "out or outside" and "[tomos], which means "to cut" or "to open". The final [-y] means "process". The suffix [-ectomy] means "process of cutting out". Other synonyms are: extirpation, excision, and removal.

Applications of this suffix include:

Pneumonectomy: Removal of a lung
Gastrectomy: Extirpation of the stomach
Nephrectomy: Excision of a kidney
Cholecystectomy: Extirpation of the gallbladder