/ Thesaurus / A Synonyms of ark shell Find synonyms for: Noun1. ark shell, bivalve, pelecypod, lamellibranchusage: marine bivalve mollusk having a heavy toothed shell with a deep boat-like inner surfaceWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: labyrinth Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language