S: (n) mouth (the externally visible part of the oral cavity on the face and the system of organs surrounding the opening) "she wiped lipstick from her mouth"
S: (n) mouth (an opening that resembles a mouth (as of a cave or a gorge)) "he rode into the mouth of the canyon"; "they built a fire at the mouth of the cave"
S: (n) mouth (the point where a stream issues into a larger body of water) "New York is at the mouth of the Hudson"
S: (n) mouth (a person conceived as a consumer of food) "he has four mouths to feed"