ostomy (plural ostomies)
- (surgery) A surgical procedure to provide an exit point for the waste of an organism.
- (medicine) An exit point created by such surgical procedure.
The conversion of the combining form -ostomy to yield the standalone noun ostomy began in the mid-20th century as medical jargon that was treated as too much a casualism for formal writing, but by the early 21st century it was well established even in formal register, and various respected dictionaries now enter it. Before this transition of acceptability, medical English already had a word for artificial bodily openings created surgically: stoma, directly from the New Latin, based on the ancient Greek. But today such an opening is just as likely to be called an ostomy as a stoma.