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to take a dump with the door locked.
there was a republican in the mall restroom with me and i was scared...
i ran into the stall and locked it behind me to make a security deposit.
by r brands August 29, 2003
Ejaculation into a condom.
Bob: I hope you used protection with that ho you banged last night.
Joe: Yeah, I made a security deposit.
by Celestial Parsnip September 04, 2003
To leave 'collatoral' or cash when someone give you drugs/goods on credit.
"Leave a security deposit if yo' are gunna have to take my money to go 'get on'."
by Diego September 05, 2003