3 Syllables: SUU
credulous, decorous, delegates, edifice, estimates, Federalist, garrulous, generous, Genesis, heritage, Methodist, Pegasus, perilous, prejudiced, querulous, recklessness, requisites, resinous, restlessness, tetanus, treacherous, venomous
4 Syllables: USUU
asparagus, confederates, degenerates, Emeritus, incredulous, preparedness, prerequisites, ungenerous
Found 30 words across 2 groupings. Skipped 1 excess word of a similar stem.