Words That Rhyme With "Pentathlon" :
2 syllables:
alan, Allan, allen, alum, ashland, balance, ballon, balun, callen, challenge, dalen, fallon, gallant, gallon, Hallam, hallan, Lallans, Mallon, palance, palen, Pathan, valance, Valens, vallance, vallum
3 syllables:
biathlon, decathlon, imbalance, outbalance, topgallant, triathlon, unbalance, ungallant, vandalen