look up any word, like b4nny:
 
1.
1.Self-Defense System.
Rex Kwin Do we use the buddy system.
No more flyin' solo.
You need somebody watching your back at all times!

2.rip-off program.
aight dawg, that show was a Rex Kwon Do.
by jiminence March 18, 2005
 
2.
A very feisty little beta fish that leaps out of his tank to bite your finger when he is hungry.
Dude, I was feedin' the rexkwondo last night, and he totally was ragin' on my finger!
by crispycritter January 18, 2011