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tips of one's hair; hair ends
毛先を丁寧に整えた。
I carefully tidied up the ends of my hair.
毛先が傷んで絡まりやすくなった。
The ends of my hair are damaged and prone to tangling.
ドライヤーで乾かす前に毛先を保護した。
I protected the ends of my hair before blow-drying.