Or search: tb, gbit, pbit, tbit, gigabit, petabit
2 Syllables: SU
desperate, Frederick, separate
3 Syllables: SUU
Arabic, Benedict, benefit, derelict, Federalists, feminist, heretic, Methodist, rhetoric, separates, specialist, terrorist, therapist
4 Syllables: USUU
inherited, unprejudiced
5 Syllables: UUSUU
disinherited

Found 19 words across 4 groupings. Skipped 3 excess words of a similar stem.