What is the meaning of the word "mouth"?

Definitions:

a person conceived as a consumer of food noun
- They have four mouths to feed.
an opening that resembles a mouth, as of a cave or a gorge noun
- We rode into the mouth of the canyon.
the externally visible part of the oral cavity on the face and the system of organs surrounding the opening noun
- I wiped lipstick from my mouth.
the opening of a jar or bottle noun
- the jar had a wide mouth
the opening through which food is taken in and vocalizations emerge noun
- They stuffed their mouth with candy.
the point where a stream issues into a larger body of water noun
- New York is at the mouth of the Hudson