/ Thesaurus / G Synonyms of guard boat Find synonyms for: Noun1. guard boat, boatusage: a boat that is on guard duty (as in a harbor) around a fleet of warshipsWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: reluctant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language