Here's what rhymes with knowun.
one done run son none sun won gun fun tion ton nun shun sion bun donne dun fon pun rien bn cen gon hun jun tonne tun ven yean naan spun undone fron seisin stun toucan anyone begun overrun outdone outrun overdone spline rerun redone misdone cretonne everyone twentyone Words that almost rhyme with knowun
some come young sum tongue hung lung cum dem sung thumb comme dumb gum rum dung hum rung wrung zum bum comm dum mum même num numb tum tung chum kung sm tem bung thrum yum from among drum flung swung clung plum slum slung stung plumb scum crumb trom glum swum unsung sebum spume become overcome sprung strung succumb overhung scrum strum benumb rehung sacrum frustum cerebrum breadcrumb simulacrum candelabrum mullein mustn fustian puncheon