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to pinch; to hold (between one's fingers); to pick up (with chopsticks, tweezers, etc.)
to pick up and eat; to snack on
to pick out (the main point); to summarize; to sum up
to bewitch; to possess; to fascinate
お寿司を箸でつまんで醤油につけた。
I picked up a piece of sushi with chopsticks and dipped it in soy sauce.
つまみ食いがばれて母に叱られた。
I got caught snacking and was scolded by my mother.
彼女はおつまみのナッツをつまんだ。
She picked up some snack nuts with her fingers.