take wing, fly up
頡 centers on upward flight: taking wing and flying up. The meanings are closely linked to the idea of rising into the air.
頡 combines 吉 (likely phonetic) with 頁 (head), but the exact historical origin of the 'fly up' meaning is uncertain. It may have originally referred to a bird taking flight, with 頁 possibly representing the head or a person looking upward.
The left side 吉 looks like a lucky charm, and the right side 頁 is a head. Imagine a lucky bird charm on someone's head suddenly sprouting wings and flying up into the sky.
For ケツ, picture a bird taking wing with a sudden, sharp motion that makes a 'ketsu' sound as it launches upward. The sound 'ketsu' cues ケツ, and the bird flies up.
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