Issac rhymes with:
kissack, lisak, lissack, mckissack, spisak, bohnsack, bolancik, borsuk, bosak, bowersock, cassock, cossack, hartsock, hosack, hossack, husak, kissack, kosak, lebsack, lisak, lissack, mckissack, orsak, osuch, prusak, prussak, russak, spisak, vlasak
Issac sounds like:
i's, i.'s, i.s, iacocca, iacocca's, iago, ice, ices, ich, ichi, ichikawa, ickes, ickes', icy, iezzi, ige, igo, igoe, igou, igushi, ihasz, ijaz, ikaes, ike, ike's, ikea, ikeuchi, ikey, ikie, ios, iosue, iowa's, is, isa, isaac, isaacks, isaacs, isaak, isaiah, isay, isch, ischo, ise, ish, ishaq, ishee, ishi, ishi's, ishii, ishikawa, isis, issa, issah, issie, issue, issue's, issues, issues', issy, isu, isuzu, iwaki, iwasaki, iwosaki, izzi, izzo, izzy, izzy's