A hinged section of an aircraft's wing which allows the aircraft to fly slower but also generates enough lift to stay aloft.
by Charlie December 6, 2004
 Get the flapsmug.
Get the flapsmug. The sound one makes when masturbateing to porn on a laptop computer. Also can be the sound mad when your pounding a honey hole and your ballsack and ramrod slam against those meaty lips.
We got home early only to walk in our apartment and hear the sound flap flap flap flap flap flaaaaaaap flap of Tim our virgin roomate wackin off to porn on his laptop.
by FLAPFLAPfromNC December 27, 2011
 Get the Flapmug.
Get the Flapmug. "Can you do me a flap for $40?"
by RealFamous August 28, 2016
 Get the Flapmug.
Get the Flapmug. “That man was flapping”
by NoFlapping April 21, 2019
 Get the Flappingmug.
Get the Flappingmug. Noun: a movement of a ballsack from side to side or up and down.
Verb: the act of using your ballsack to hit something
Verb: the act of using your ballsack to hit something
by Electrified22  October 15, 2018
 Get the Flapmug.
Get the Flapmug. 
