Or search: pack, rename, appoint, propose
3 Syllables: SUU
commonest, commonplace, compensate, concentrate, consummate, contemplate, cooperate, dominate, moderate, novelist, oftenest, operate, oscillate, propagate, proselytes, tolerate
4 Syllables: USUU
accommodate, conglomerate, corroborate, denominate, exonerate, geologist, predominate, psychologist

Found 24 words across 2 groupings. Skipped 12 excess words of a similar stem.