A cakehole is a pejorative term in English slang for the mouth of a person who is thought to be speaking offensively or nonsensically, or who is attempting to participate in a conversation out of turn.
Though now fallen somewhat into disuse, and perhaps considered archaic, the term originated in the United Kingdom, its peak use spanning from the middle of the 20th century to the 1970s. The 1943 reference book Service Slang by Hunt and Pringle (a humourous reference manual on the language used by the British Army, Navy, and RAF during the Second World War) explains the term, "Cake hole, the airman's name for his or anyone else's mouth."
The equivalent term 'piehole' first saw use in the 1980s in the United States, though it is unclear if it was coined independently, or if it was derived from cakehole.
Other equivalent terms are gob, trap, yap, and face, all of which can be used identically in the "Shut your ___!" (and most of which can fit into "Stuffing your ___") formation with no substantial change in meaning.
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