Wiliams rhymes with:
petroleum's, abiam's, aquariums, atriums, auditoriums, axioms, caladiums, condominiums, consortium's, geraniums, gymnasiums, herbariums, honorariums, idioms, mediums, millenniums, moratoriums, pentiums, petroleum's, podiums, premiums, stadium's, stadiums, symposiums, zirconiums
Wiliams sounds like:
wailing, walinsky, walling, wallowing, wehling, welinsk, wellens, welling, wellness, wellons, whaling, wheeling, wheeling's, wholeness, wilensky, wilhelms, wiling, wilinski, willaims, willems, willens, william's, williams, williams', williams's, willing, willms, wilmes, wilms, wolanski, wolenzac, wolenzac's, wolinski, wolinsky, woolens, woolums