/ Thesaurus / C Synonyms of combined operation Find synonyms for: Noun1. combined operation, operation, military operationusage: a military operation carried out cooperatively by two or more allied nations or a military operation carried out by coordination of sea, land, and air forcesWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: effervescent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language