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to flip; to snap; to flick
to repel
to use (an abacus); to calculate
to strum; to pluck the strings (of a guitar, etc.)
「弾く」 has another reading with different meanings.
子供たちが指で水を弾いて遊んでいる。
The kids are playing by flicking water with their fingers.
そろばんの玉を弾いた。
I flicked the beads on the abacus.
雨粒が傘の表面で弾かれる。
Raindrops bounce off the surface of the umbrella.