look up any word, like ratchet:
 
1.
describing someone who is under intense or extreme pressure.
I was under the gun to get that project done on time.
by hipster November 27, 2005
 
2.
The first person to act in a betting round of poker.
I was under the gun with a pair of jacks.
by Naterz September 26, 2005
 
3.
A situation in which a person is pressured into performing oral sex.
Tim and Erica had been dating for a few months. Tim told Erica to give him oral sex. She then found herself "under the gun."
by hesgotjokes March 27, 2011