/ Thesaurus / T Synonyms of third rail Find synonyms for: Noun1. third rail, track, rail, rails, runwayusage: a rail through which electric current is supplied to an electric locomotiveWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: profiterole Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language