The briefest possible act of sexual intercourse. There is no "pumping" involved - just insertion, ejaculation, and withdrawal.

Although very similar physically to a "one-pump wonder," but a flu shot is different because it is a deliberate act meant to save time. A flu shot requires training to accomplish correctly. A flu shot is a valuable scheduling tool.

Men generally enjoy giving flu shots more than women enjoy receiving them, but with discipline women should be able to train their bodies to orgasm from a single flu shot.
I joined the mile high club when I gave my girlfriend a flu shot in the bathroom right before the plane landed.
by November 20, 2010
While having sex doggy style, the person doing the jack hammering chugs a gallon of milk. The gyration of the body with the souring of the milk in the stomach will induce vomiting. This will need to be timed perfectly with ejaculation. While the shot goes inside of the vagina, the flu like vomit goes all over the back.
"Last night i gave my girl a flu shot and i dont think that she liked me cumming inside her or my puke on her back."
by Johnson1981 April 1, 2016
When you cum in a girls mouth and then tell her a joke to make her laugh, which causes your cum to come out her nose.
On a second date I gave this girl a flu shot. Still haven’t heard back...
by Hank Hardister Comedy March 13, 2019
When you've had enough of someone. So you take a pen and preferably stab them in the eye or somewhere else on the body.
"Man this customer wont stop fuckin' complaining about this bread. Imma give em' a flu shot!"
by McCreazy February 6, 2008
A non-medical term for the 3-5 days of feeling like crap after you get your flu shot.
Dude 1. Hey, what’s wrong with you? You look like shit.
Dude 2. I also feel like shit. I got my flu shot yesterday, now I have flu shot flu.
by Ski25 November 13, 2011
The guilt projected onto a person that doesn't want to or believe in taking the flu shot vaccine.
You say "No" meaning "I don't want you to inject me with formaldehyde & mercury" and the nurse gives you the flu shot guilt by sending you a look like you just said "there's no such thing as God."
by Veritas Caput January 19, 2012
Cheap bourbon and Nyquil, served lukewarm in a shot glass.
Last year I started feeling sick, so I took 3 Redneck Flu Shots. Woke up 4 days later in a puddle of my own drool. Felt great though.
by freeman42 January 18, 2012