mouth A1

/maʊθ/ The opening in your face that you use for eating and speaking.

bigmouth C2+

/ˈbɪɡˌmaʊθ/ a loud, talkative person who reveals secrets

mouthful C2+

/ˈmaʊθfʊl/ an amount of food or drink that fills the mouth; a long or hard-to-say word