/ Thesaurus / B Synonyms of bbl. Find synonyms for: Noun1. barrel, bbl, United States liquid unit, British capacity unit, Imperial capacity unitusage: any of various units of capacity; "a barrel of beer is 31 gallons and a barrel of oil is 42 gallons"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: lyre Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language