noun Ralph Wal·do, [wawl-doh, wol-] /ˈwɔl doʊ, ˈwɒl-/, 1803–82, U.S. essayist and poet. nounRalph Waldo. (rælf ˈwɔːldəʊ). 1803–82, US poet, essayist, and transcendentalist