Fountaine rhymes with:
buntain, contain, fontaine, lafountain, lafountaine, lamontagne, maintain, abstain, aquitaine, ascertain, attain, brattain, buntain, butane, chastain, contain, costain, detain, entertain, fontaine, lafountain, lafountaine, lamontagne, maintain, mustain, obtain, partain, pertain, petain, retain, sartain, stain, sustain, uptain
Fountaine sounds like:
fantini, fanton, fenton, finton, fontaine, fontana, foundation, fountain, funtime