WordNet sense 1 (a confused multitude of things):

clutter, fuddle, jumble, muddle, welter, mare's nest

WordNet sense 2 (deprive of oxygen and prevent from breathing):

asphyxiate, suffocate

WordNet sense 3 (deprive of the oxygen necessary for combustion):

put out

WordNet sense 4 (envelop completely):

surround

WordNet sense 5 (conceal or hide):

muffle, repress, stifle, strangle, repress