Green Dot is a line of prepaid universal gift cards sold at places that typically sell gift cards.

These cards claim to be "safer than cash" but they've got cheesiness writen all over them; people with stolen credit cards or forged $100 bills have a tendency to load these cards to the maximum amount. To add to the frustration a person who uses it legitamately is typically left angered after cashiers at several locations don't know what the hell to do with the cards.

Originating from the game Call of Duty: Modern Warfare 2 it was used to describe a teammate whom you do not know. These team mates will show up on the radar map as green arrows or “Green Dots”. Often used during times of anger or frustration when a fellow team mate is doing something that offends you, “Green Dot” could be shouted over a microphone to encompass any one of the people on your team in hopes that the one committing the offensive action would hear you and stop what they were doing.

Green Dot can also be used in real life to describe others around you that you do not know or are not acquainted with. This includes people at the park, at school or a party.