asshat

asshat

rude slang A jerk. This phrase plays on another expression, "have (one's) head up (one's) ass," which means to act in a way that others deem stupid or obnoxious. This phrase evokes the image of someone using their buttocks as a hat. Quit being an asshat and help me with this! Ugh, that guy is such an asshat—don't even bother talking to him.
Farlex Dictionary of Idioms.

asshat

1. n. the imaginary garment worn by one with one’s head up one’s ass. (Offensive.)
2. n. a person said to be wearing an asshat (sense 1). Wake up you stupid asshat!
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • show (one's) butt
  • yazzihamper
  • pain in the hole
  • catch on with (one)
  • megabitch
  • catch on
References in periodicals archive
They will be my words not a PR persons." He then added, "You don't know me and have no reason to think I am anything but an 'asshat.' But I feel terrible and I am truly very sorry."
I was certainly not blameless in all of this, and said how sorry for how I conducted myself, especially for the gratuitous "asshat" statement.
Padres CEO Tom Garfinkel Goes the Extra Mile After 'Rain Man' Comment
The New Yorker, known throughout the field of journalism for its erudite take on politics and humor, tweeted earlier this month, "As much as President Obama wants us to call Mitt Romney 'Romney Hood,' I'm going to stick with my nickname for him, 'F--king Asshat.'"
The new home of Andy Borowitz: the former newspaper columnist takes his talents to The New Yorker
Greenspan is--let's face it--quite the asshat himself.
The Rumpleville Chronicles: The Jolly Elf The Bomb That Followed Me Home The Disciples of Trotsky
Greenspan is let's face it quite the asshat himself.
The Rumpleville Chronicles: The Jolly Elf, The Bomb That Followed Me Home, The Disciples of Trotsky