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index finger; forefinger; first (occ. second) finger
second toe
人差指で方向を指して道を教えてくれた。
They pointed with their index finger and showed me the way.
人差指にできたあかぎれが痛くてたまらない。
The chapped skin on my index finger hurts terribly.
彼は人差指を唇に当てて静かにと合図した。
He put his index finger to his lips and signaled to be quiet.