Doomsayers rhymes with:
naysayers, sayers, soothsayers, ayars, ballplayers, bayer's, bayers, beyers, breyer's, layers, maiers, mayer's, mayers, mayor's, mayors, naysayers, payer's, payers, payers', player's, players, players', purveyors, sayers, soothsayers, sprayers, surveyor's, surveyors, thayer's, thayers, weyers, zayre's
Doomsayers sounds like:
dancer's, dancers, dancers', dangerous, dangers, democracies, democracy, democracy's, denigris, dinosaurs, dunkirk