Or search: gassy, aeriform, vaporish, gasified, vaporized, vaporific, vapourish, vapourous, evaporated, vapourific, vapourised, volatilised, volatilized
2 Syllables: SU
asses, batches, Cassius, classes, fastest, gases, glasses, grasses, gravest, habeas, happiest, masses, matches, passage, passes, patches, rashness, savage, scratches, vastness
3 Syllables: SUU
happiness
3 Syllables: USU
Damascus, disastrous, Erasmus, molasses, Parnassus
4 Syllables: UUSU
instantaneous

Found 27 words across 4 groupings.