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to tilt (esp. head); to lean; to incline; to slant
彼かれは首くびを傾げかしげた。
He tilted his head.
彼女かのじょはいつも首くびを傾げるかしげる。
She always tilts her head.
不思議ふしぎそうに首くびを傾げかしげていた。
He was tilting his head as if puzzled.