Or search: foe, rival, foeman, opposer, opponent, besieger, resister, contender, antagonist, challenger, competitor
3 Syllables: SUU
charities, clemency, destinies, elegies, enemy, enemy's, Genevieve, heresies, jealousies, legacies, melodies, memories, parodies, pedigrees, Pericles, recipes, remedies, reveries, tenancy, tendencies, tendency, treasuries, verities
4 Syllables: USUU
accessories, amenities, ascendancy, ascendency, barbarities, dependencies, dependency, disparities, extremities, hegemony, inclemency
5 Syllables: UUSUU
independency, independently, similarities
6 Syllables: UUUSUU
irregularities, peculiarities

Found 39 words across 4 groupings.