A slang term to befriend someone or try to get closer to someone.
Example 1:
Person 1: "I had beef wid that foo cuz i knew he was gonna fuck me up so I gained pounds wid him so he can back me up instead.

Example 2:
Person 1: "Ey foo, check out that chick over there. GO gain pounds wid her nigga"
Person 2: "Aight my dude, Imma go gain pounds wid her then"
by Howard Tan April 27, 2006
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