A phenomenon that serves as a sign or warning of some future good or evil:augury, forerunner, foretoken, omen, prefigurement, presage, prognostic, prognostication, sign. Idiom: writing (or handwriting) on the wall. See foresight, warn Roget's II The New Thesaurus Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.