Here's what rhymes with protogon.
gone con khan don non von dawn lawn yon hon wan bon fawn han pawn schon yawn bonne sawn sonne vpon begone pecan faun john autobahn gnawn upon drawn baton spawn swan yuan exon brawn forgone prawn tenon woebegone neocon undergone thereon polygon salon foregone whereon octagon paragon redrawn chiffon pentagon aileron hereon predawn tarragon lasagne emoticon outdrawn lexicon denouement pantheon rapprochement echelon chaperon overdrawn amazon antiphon epsilon carillon leprechaun heptagon cordovan trimaran upsilon withdrawn thereupon whereupon automaton positron hexagon marathon hereupon mastodon frogspawn methadon pantechnicon phenomenon Words that almost rhyme with protogon
com calm gong long wrong song bomb palm mom quam bom homme vom balm nom rom som tom dong mam thong pom pong tong bong qualm iamb becalm along belong throng prom prong pogrom twang sarong strong prolong intercom aplomb embalm salaam consomme erelong mahjong dingdong lifelong singsong livelong yearlong nightlong firebomb supermom cardamom corn born borne torn worn barn horn warn scorn yarn morn mourn thorn shorn darn porn tarn lorn sworn adorn lowborn forlorn unborn reborn outworn unicorn waterborne careworn forborne forewarn peppercorn timeworn unworn stillborn forsworn lovelorn foresworn sweetcorn firstborn