Here's what rhymes with semigaseous.
gaseous Words that almost rhyme with semigaseous
cassias habeas canniness glassiness classiness happiness malleolus dalliance nastiness ghastliness patchiness tackiness bassinets palliates valiance bagginess brassiness chattiness shagginess cragginess fattiness faddiness nattiness sappiness pancreas craftiness scantiness scratchiness snappiness instantaneous transience pantheists retaliates draftiness transients bathyscaphs