muffle

(noun) a kiln with an inner chamber for firing things at a low temperature.

(verb) conceal or hide. Synonyms: smother, stifle, strangle, repress. Examples: "Smother a yawn." "Muffle one's anger." "Strangle a yawn."

(verb) deaden (a sound or noise), especially by wrapping. Synonyms: mute, dull, damp, dampen, tone down.