Underdog rhymes with:
bulldog, gundog, hotdog, lapdog, watchdog, analog, analogue, bulldog, bullfrog, catalogue, dialogue, eggnog, epilogue, gundog, hotdog, lapdog, leapfrog, metagogue, monologue, sandhog, synagogue, travelogue, watchdog
Underdog sounds like:
underdogs, undertake, undertakes, undertook, undertows, underwoods, underwrites, unitrode's, untruths