look up any word, like rockabilly girl:
 
11.
Assimilation of a lot of information and forgetting it as soon as the necessity for learning it is over. Originates from filling the fuel tanks of an aircraft, taking off, and then immediately dumping the fuel prior to landing in order to (1) train using the dump valve, (2) use up the squadron's allocation of fuel so that the allocation will not be reduced the next year (especially popular at the end of the fiscal year), and (3) ensure a safe landing (most aircraft cannot safely land full of fuel).
I will have to pump and dump for the engineering exam next week, since I have a multi-d final two days later.

We have to go through 500,000 pounds of fuel in the three days before October 1. It looks like we'll be flying nothing but pump and dumps.
by Navyd September 03, 2008
 
1.
Similar to a one night stand. One who purposely fornicates with another, while not intending to see them in the future. Like a conquest.
Chad: "Dude, I scored a hot piece of ass last night!"

Ken: "What, is she like your girlfriend now or something?"

Chad: "Naw man, it was just a pump and dump scenario. I've got a date with Buffy tonight."
by Angela Wallenbrock, MD November 02, 2007
 
2.
one night stand

When a man has sexual intercourse with a woman, and then breaks up with her (if they are in a relationship) or never speaks to or makes contact with them again after the aforesaid act.
Tom:- Did you go to that party last night?

Ollie:- Yeah, I did that fit girl from Wells Hall. She was so good. She know's how to f**k.

Tom:- Did you get her number?

Ollie:- Naa, I just pumped and dumped her. What's her name again?

Tom:- You're such a man slag. You allways pump and dump
by The Master of Definitions January 23, 2006
 
3.
act of shitting and jerking off at the same time
i only had five minutes alone in the bathroom so i had to pump and dump
by the filty whore November 14, 2009
 
4.
To pump and dump a load in a hot hole and leave. Usually referring bareback sex (anal sex without a condom). A breed and bail
Dude, up for a pump and dump?

That would be great... have a few before work
by rawfcknpig January 16, 2010
 
5.
To pump a stock that you own and dump it when the price goes up.
Stay away from QBID it is a pump and dump.
by Fred Silvia September 10, 2005
 
6.
A fast, unprotected sexual meeting between two gay men, where the top "pumps" the bottom and "dumps" his ejaculate inside the receiver.
I need to get off, know anyone up for a quick pump and dump?
by LChamp December 08, 2006
 
7.
when a guy has sex with a girl with the intent to only get a nut. it consists of 1 - 5 pumps or thrusts followed by ejaculation (dump his load) followed by the departure of the male to go back to the party or wherever it was that he met the victim of the "pump and dump"
much to sallys displeasure, her and jacks sexual experience at keegans party consisted of only a pump and dump in the bathroom.
by SMairlines May 22, 2009