Oligarchy rhymes with:
hierarchy, matriarchy, patriarchy, archey, corky, darcie, darkie, decourcy, demarchi, gorki, gorky, harkey, hierarchy, horkey, horky, lamarche, larkey, malarkey, marchi, marcie, markie, marky, matriarchy, monarchy, mullarkey, orky, patriarchy, piercy, porky, sharkey, shorkey, sparky, sterchi, trimarchi, turchi