Here's what rhymes with sixthfifth.
fifth Words that almost rhyme with sixthfifth
sieves scythes riffs skiffs sniffs whiffs stiffs gives lives myths cliffs smiths writhes clefs withes forgives mastiffs silversmiths gunsmiths goldsmiths hieroglyphs blacksmiths monoliths filth scythe myth sixth width pith smith writhed writhe plinth hyacinth forthwith therewith herewith silversmith labyrinth wherewith monolith