Fatty rhymes with:
attie, battey, batty, catty, chatty, cincinnati, cratty, gatti, gatty, hattie, hatty, latty, mattie, matty, mcatee, nattie, natty, patti, pattie, patty, ratty, tatty
Fatty sounds like:
f'd, fad, fade, faded, faeth, fahd, fait, faith, fat, fata, fatah, fate, fated, fateh, fath, fathi, fatwa, fauth, favata, fayed, fayette, feat, fed, fede, fedewa, fediay, feed, feet, feit, feith, fete, feted, fetid, fett, fette, fetty, feud, feuded, fiat, fiato, fidata, fide, fido, fiftee, fifth, fiftieth, fifty, fit, fite, fithe, fitt, fitted, food, foodie, foodway, foot, foote, footed, foth, foti, fouad, fout, fouty, foyt, fuddy, fudo