/ Dictionary / Index W water rail: Meaning and Definition of Find definitions for: wa'ter rail" Pronunciation: [key] an Old World rail, Rallus aquaticus, having olive-brown plumage marked with black and a long, red bill. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. waterproofing water rat Related Content Daily Word Quiz: acquiesce Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language