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to swipe; to nick; to pilfer
to greedily try to win big (e.g. in mahjong)
つり銭をがめる店員がいた。
There was a clerk who pocketed the change.
彼は友達のゲームソフトをがめている。
He's swiping his friend's video game.
あいつ、また菓子をがめたな。
That guy swiped the snacks again.