boasting, fortunate, beautiful
烋 centers on a sense of overflowing excellence: it can mean boasting (displaying one's good fortune) or being fortunate and beautiful. The meanings are loosely connected by the idea of something conspicuously good.
烋 combines 休 (rest) with 灬 (fire). The exact historical development is uncertain; it may have originally expressed a sense of flourishing or blazing, but the connection to the given meanings is not clearly established.
A person (亻) resting (休) by a fire (灬) might feel fortunate and beautiful, or boast about the warmth. The fire's glow makes everything seem excellent.
For コウ, imagine a person boasting by the fire, saying 'I'm so コウ (like 'co' in 'cozy') and fortunate!' The cozy fire scene helps recall コウ.
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