jerkoff

From the verb jerk off (“masturbate”).

jerkoff (plural jerkoffs)

1. (idiomatic, vulgar, colloquial) Someone who behaves obnoxiously, rudely, inappropriately, or is ignorant of certain social norms, usually a male.
   • 1998, Adam Sandler as Robbie Hart, The Wedding Singer, written by Tim Herlihy:

     I think she's a very nice girl, but she's marrying that jerkoff.

   • 1992, Eric Lee, Saigon to Jerusalem: conversations with U.S. veterans of the Vietnam War who ..., page 25:

     All New Yorkers have this feeling that anyone who's not from New York is a jerk-off. And I couldn't believe that someone had the balls to shoot at me.

2. (idiomatic, vulgar, rare) Someone who masturbates, usually a male.
   • 1935, Lawson Gentry Lowrey, “Proceedings of the 8th- annual meeting of the American Orthopsychiatric Association”, in American journal of orthopsychiatry, Volume 5‎ - Page 279, volume 5, page 279:

     Slob or Slop for a dirty child, Beans for a child who breaks wind, Jerk-off for a child who masturbates.