Words That Rhyme With "Addendum" :
2 syllables:
Adam, bedlam, beldam, beldame, Brendan, Breton, cecum, Dedham, ebben, Eben, ebon, Edam, Edom, Edson, eggen, elden, Emden, freedom, headen, headman, jetton, leaden, leben, leedom, madam, Meghan, modem, Needham, odum, redden, redken, Regen, rodham, Saddam, sedum, seldom, Sheldon, Sodom, steadman, tendon, threaten, vegan, welden, Weldon
3 syllables:
agendum, Hasidim, macadam, Tibetan
4 syllables:
Armageddon, corrigendum, referendum, tarmacadam