A general term used to indicate someone attempting to take advantage of someone else or play them in a scam, be it something simple, like beating one to a parking space, or complex, like criminal fraud.

Past tense: got over on

Not to be confused with "get over" oneself spoken to a pretentious person.
> Your boss is trying to get over on you. He just took that report you spent three months writing, erased your name and put his on it. Looks like he'll get a big bonus for it.
> My former tenants really got over on me. They stopped paying rent, so I had to take them to court and evict them. It took months and cost me tens of thousands of dollars in lost rent, hiring a lawyer, and repairing the damage they caused. Meantime they lived in a three bedroom house for only two months' rent.