[f. BANG sb.2] To cut (the front hair) square across, so that it ends abruptly.

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1882.  Century Mag., XXV. 192. He was bareheaded, his hair banged even with his eyebrows in front.

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1883.  Harper’s Mag., March, 492/2. They wear their … hair ‘banged’ low over their foreheads.

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