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