It is a conjunction of the phrase "let's go." First used on the television show King of the Hill by Dale Gribbel. Preferably used repeatedly and increasingly intense.
Dude came to your house to see if you wanted to chill, since you wouldnt answer your phone. When i got there your mom was there drunk. She came onto me and i got her shirt off!!! Sco!!
By Ysabel
Sco
Verb: to do whatever it takes (assert, deny, obfuscate, fabricate, deceive, procrastinate, tapdance, exhort, cyberterrorize, etc) in order to create a truly convincing alternate reality, fully operational in a paralegal universe and immune to all known forms of US litigation.
