Or search: ape, jerk, loon, mortal, someone, somebody
2 Syllables: SU
Bridget, civic, digit, district, drifted, gifted, lifted, listed, livid, mystic, mythic, physic, rhythmic, rigid, shifted, sifted, twisted, visit, vivid
3 Syllables: USU
artistic, assisted, consisted, desisted, elicit, enlisted, insisted, linguistic, Pacific, persisted, prolific, realistic, resisted, revisit, simplistic, solicit, specific, statistic, stylistic, subsisted, terrific
4 Syllables: UUSU
altruistic, atheistic, Calvinistic, communistic, fatalistic, hieroglyphic, humanistic, idealistic, journalistic, logarithmic, mechanistic, metaphysics, monolithic, nationalistic, naturalistic, optimistic, pessimistic, rationalistic, scientific, socialistic, unassisted, unrealistic
5 Syllables: UUUSU
antagonistic, capitalistic, characteristic, monopolistic, ritualistic, unscientific
6 Syllables: UUUUSU
imperialistic, materialistic
7 Syllables: UUUUUSU
individualistic

Found 71 words across 6 groupings. Skipped 10 excess words of a similar stem.