Here's what rhymes with onlythree.
three free ye li flee lee ri ry flea lea yi lii rhe be he we me she t de see d p pp b c sea v ve key tree di g pre tea thee fee knee ne si z bee mi plea te vii je ni sie ti tlie wee xi xii xiii ci esprit fc fhe glee hee hie ki nee pea ski tee wi wie dd dy gi gli hae ji mea mee ny quay shi shih sv thi whieh ze alii bb chih dee fea fie gee ghee lhe nae nie pari pee prix qi rny sae sci shee spree tiie tke xy zi scree saree brie whee sirree degree agree decree qui ac cc dc xvi xvii cd exp foresee lessee tc xxi xxii xxiii bc kb referee rupee sd sibi xxvi xxvii xxxi bailee quis xxxii xxxiii xxxvi xxxvii queerly settee ranee suttee twee wormy epee fusee enlistee florae yippee trustee debris disagree marquis db oversee pc pg tp trainee appellee bt donee dp ftp jt marquee pd tb tv vendee amphorae bowsprit goatee oversea retiree tepee bursae curie parolee prithee artsy aurorae emcee escapee invitee returnee teepee draftee honoree sudsy topee whoopee footsie puttee soignee sultrier wintrier shoetree http nobody mit devotee mortgagee nominee addressee assignee grantee interviewee jubilee licensee quelque apogee legatee pensee repartee filigree abscissae banshee honeybee manatee potpourri gutsy internee monody quinsy colossally conferee jamboree kedgeree tootsie whiffletree paltrier guarantee absentee guaranty phonology appointee diastole hyperbole transferee tympani franchisee undersea amputee detainee timpani attendee calliope wannabe deportee dungaree inductee guarani maharanee wannabee bourgeoisie consignee bumblebee axletree chiropody abductee singletree whippletree idiosyncrasy