/ Thesaurus / R Synonyms of railroad flat Find synonyms for: Noun1. railroad flat, apartment, flatusage: an apartment whose rooms are all in a line with doors between themWordNet 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