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3.
GSI
An acronym for a "generic sexual inuendo".
"Thats what she said" is a GSI
by Trevor Davis 69 June 18, 2010
 
1.
GSI
Graduate Student Instructor. Terminology used at UC Berkeley.
My GSI was able to help me in the discussion portion of the class.
by Go Cal!!!! June 09, 2009
 
2.
GSI
Synonym of SIF (secret internet fattie) for the Spanish Gorda Secreta de Internet.
"Hey Erdos, I believe this OkCupid profile is GSI compliant."

"Yeah, look at that strategic camera angle"
by MeherBaba April 24, 2007
 
4.
GSI
Google Search It
"Where can I get that video you sent me?"
"GSI"
"Thanks."
by Mutank March 03, 2009
 
5.
GSI
Is an acronym for the Greer Sucks Initiative. To show a webpage or product supports the initiative, put the following somewhere in the document:

This page is GSI Compliant
Jay> Man, did you see that transformer explode all over Greer's Accord?
Wes> Yup, I wonder why he parked under it?
Jay> I know why!
Wes> Why?
Jay> Greer Sucks!
by GsiCommish October 13, 2004
 
6.
GSI
acronym for "Get Stuck In" or "Get Sexual Intercourse"
Sam: I'm away to talk to Amy

James: GSI dude
by JTJP March 16, 2007