pop

   1. to ingest narcotics illegally

   Either from popping them into your mouth as a pill or into vein by injection. Whence popper, such a pill or injection:

    The ammoniac aftersmell of poppers hung in the air. (M. Thomas, 1982)

   2. an act of copulation

   Possibly from the sensation of orgasm, but more likely because pop can be a synonym of go, meaning a single occasion:

    Azalo figured she'd be lucky to get twenty bucks a pop. (Sanders, 1985 — Azalo was a prostitute)

   To pop is to copulate, of a male:

    Someone [the Candidate] popped at the 1984 convention. (Anonymous, 1996)

   3. to pawn

   Perhaps from popping in to effect the transaction with uncle:

    I had to pop the silver, you know what I mean. (Guinness, 1985)

   And in the old song:

    Up and down the City Road,

   In and out the Eagle.

   That's the way the money goes.

   Pop goes the weasel.

   The Eagle was a London public house of which a former landlord was the father of one of my aunts by marriage, a shameful connection of which other family members were long kept unaware. The weasel was the weasel and stoat, overcoat.

   4. to kill

   Causing another to POP OFF or from the sound of the gun?

    We don't pop people any more. We've learned from the Argentines. People just disappear. (Sanders, 1984)