/ Thesaurus / J Synonyms of japanese leek Find synonyms for: Noun1. Welsh onion, Japanese leek, Allium fistulosum, onion, onion plant, Allium cepausage: Asiatic onion with slender bulbs; used as early green onionsWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: panacea Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language