straight
頲 centers on the idea of straightness, likely referring to a straight posture or upright bearing. The single given meaning is narrow, and the kanji is rare, so treat its core as physical straightness.
頲 combines 廷 (court, straight) with 頁 (head), suggesting a straight or upright head posture. The exact historical development is uncertain, but the phono-semantic structure is plausible.
The left side 廷 suggests a straight court or hall, and the right side 頁 is a head. Imagine a court official holding their head perfectly straight and upright.
For テイ, picture a straight table (テーブル, teeburu) where the court official rests their head: table -> テイ, and the head stays straight.
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