sti·fle 1 
(stīfəl)
(stīfəl)tr.v. sti·fled, sti·fling, sti·fles
1. To interrupt or cut off (the voice, for example).
2. To keep in or hold back; repress: stifled my indignation.
3. To kill by preventing respiration; smother or suffocate.
[Middle English stifilen, alteration (influenced by Old Norse stīfla, to stop up) of stuffen, stuflen, to stifle, choke, drown, from Old French estoufer, of Germanic origin.]
stifler n.