Amex's rhymes with:
genex's, index's, indexes, patlex's, royex's, syntex's, affixes, alex's, alexs, amax's, annexes, apex's, appendixes, avtex's, axes, banks's, boomboxes, brooks's, cevaxs, cineplex's, climaxes, coaxes, comex's, cox's, crucifixes, cyrix's, dax's, dynamics's, endotronics's, essex's, exes, faxes, felix's, fixes, flexes, gearboxes, genex's, hoaxes, imax's, index's, indexes, ionics's, isomedix's, jukeboxes, knox's, lynxes, mailboxes, marks's, matchboxes, matrix's, matrixes, max's, metroplexes, miramax's, nixes, nynex's, onex's, outfoxes, paradoxes, patlex's, perplexes, phoenix's, relaxes, royex's, sachs's, saks's, six's, sixes, skyboxes, sox's, speakes's, spinks's, surtaxes, syntex's, tax's, taxes', telex's, telmex's, vaxes, waxes, wickes's, x's, x.'s, x.s, xerox's, xeroxes
Amex's sounds like:
aeneas, ahmeek, aim's, aiming, aims, ainge, am's, amasa, amass, amasses, amax, amax's, amaze, amazes, amc, amca, ameche, amenaces, ames, ames', ames's, amex, amexco, amexco's, amezcua, amick, amico, amicus, amiga, amigo, amigos, amis, amish, amiss, ammons, amnesia, amnesiac, amoco, amoco's, amok, among, amos, amos's, amoskeag, amoskeag's, amoss, ams, amsco, amuck, amuse, amuses, amy's, amyx, anac, anas, anasazi, ancho, anemias, anemic, ang, ange, angi, angie, angio, anguish, angus, angy, aniak, animous, animus, anise, anja, ankh, ann's, anna's, annamese, annas, anne's, annese, annex, annexes, annick, annie's, annis, announce, announces, annoyance, annoyances, annoying, annoys, annunzio, anonymous, ansa, ansa's, anse, anus, anxious, anyone's, anyways, anza, anzio, anzus, aoun's, aung, auyeung, awning, aynes