Or search: dive, sport, breather, athletics, submarine, schnorkel, schnorchel
2 Syllables: SU
choral, coral, cordial, corporal, dorsal, floral, forceful, formal, laurel, moral, morsel, mortal, mournful, normal, oral, Oriel, portal, quarrel, quarrelled, quarrels, scornful, sorrel
3 Syllables: USU
abnormal, armorial, corporeal, immoral, immortal, informal, memorial, pictorial, primordial, resourceful
4 Syllables: UUSU
dictatorial, editorial, equatorial, immemorial, senatorial, territorial
5 Syllables: UUUSU
inquisitorial

Found 39 words across 4 groupings. Skipped 10 excess words of a similar stem.