Fast rhymes with:
aghast, amassed, assed, ast, bast, blast, cast, caste, classed, gassed, gast, glassed, grassed, harassed, hast, kast, lambaste, last, lymphoblast, massed, mast, miscast, nast, passed, past, precast, rast, recast, surpassed, unsurpassed, vast
Fast sounds like:
facade, faced, facet, faceted, fachet, fact, facteau, facto, faggot, fagoth, faist, fajita, faked, fascist, fassett, fasted, faucet, faucett, faucette, faught, fausett, faust, fausta, fausto, fawcett, faxed, fazed, feast, feasted, fecht, fecteau, feight, feist, feisty, fekete, fessed, fest, festa, feucht, fewest, fickett, fiest, fiesta, fight, fischetti, fisette, fished, fist, fisted, fivecoat, fixate, fixated, fixed, focht, focused, focussed, foggiest, fogt, foist, foisted, foskett, fossett, fought, foust, foxwood, fucked, fugate, fugett, fugitt, fujita, fukuda, fused, fussed, fust, fustat