Breadcrumb Home > Thesaurus > C Synonyms of clastic rock Find synonyms for: Noun1. clastic rock, rock, stoneusage: (geology) a rock composed of broken pieces of older rocksWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. ✖ Related Content Daily Word Quiz: ultimathule Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language