Westerdam's rhymes with:
amsterdam's, amsterdam's, amsterdam's, amsterdam's, abrahams, amsterdam's, cunningham's, diagrams, electrocardiograms, histograms, holograms, kilograms, logjams, logograms, mailgrams, mammograms, micrograms, milligrams, oxfam's, polygram's, priam's, program's, programs, programs', reprograms, sonograms, telegrams