surgical procedure vs surgical operation

surgical procedure and surgical operation both are nouns.

Word	Noun	Adjective	Verb	Adverb
surgical procedure	Yes	No	No	No
surgical operation	Yes	No	No	No

As nouns, surgical procedure and surgical operation are synonyms defined as:

surgical procedure and surgical operation: a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body

Other synonyms of surgical procedure include operation, surgery, surgical process.

surgical procedure (noun)	surgical operation (noun)
a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body	a medical procedure involving an incision with instruments; performed to repair damage or arrest disease in a living body