look up any word, like sapiosexual:
 
1.
This occurs during the lake season while a girl, preferably in a small bikini, goes tubing. The previously mentioned girl is sitting up right and as the boat goes around a turn one leg slips off the side into the water and the other stays on giving 30 mph water a straight shot at her vagina, instantly cleaning it out of all dirtyness.
"Dude, Sam, did you see Kaitlyn get that instadouche at the lake last weekend?"

"Yeah I might actually eat her out now."
by youwillneverguessme February 16, 2012
 
2.
when you're one person and then your significant other arrives and your evil side comes out to impress them.
Man, he was so cool until bitch showed up and he became an insta-douche, just so he could get some.
by missspiffy September 12, 2011
 
3.
a tall, lanky, austrailian douchebag.
You're an "insta-douche" for taking up six washers.

Dude! You used pacifism and arrest on 8 of my creatures! You're such an insta-douche!
by Jace Beleren February 10, 2011