Definition & Meaning of "cock holster"in English

What is the origin of the term "cock holster" and how is it used?

"Cock holster" is a crude slang term from late 20th-century English used to insult a person's mouth, implying it is used for holding or servicing penises. The term combines "cock," a vulgar term for penis, with "holster," suggesting a holder or receptacle, creating a graphic sexualized metaphor meant to demean or humiliate. It appears almost exclusively in informal, hostile, or sexually explicit contexts, such as insults, adult humor, or online arguments. The term is highly vulgar and derogatory, intended to shock, insult, or provoke.