Here's what rhymes with portemanteau.
canto tanto panto quanto Words that almost rhyme with portemanteau
banjo bandeaux campo commando piano facto macro mallow matzo nacho shadow shallow fallow barrow gastro mango tallow harrow salvo basso callow hallow lasso backhoe hallo wacko tobacco fiasco cilantro intaglio tango ticktacktoe overshadow foreshadow scarecrow fandango gazpacho