It is a term that is often used in connection with slash fanworks. In literary works of the RPS category the abreviation for the pairing Jensen/Jared is JSquared.
I read this great JSquared fic on the SPN RPSLJ community.
Nickname given to bales of marijuana thrown overboard or out of airplanes. Origin is reportedly from members of the US Coast Guard in the area of Southern Florida.
"Base we've got some square groupers floating outside of Miami harbor."