crane (bird)
寉 centers on the crane, a tall wading bird. The meaning is straightforward and specific to this bird.
寉 is an older form of 鶴, combining 宀 (roof) and 隹 (bird), possibly suggesting a bird under a roof or a tall bird. The exact historical development is uncertain.
Under a roof 宀, a bird 隹 stands tall like a crane. Picture a crane stretching its long neck inside a high-roofed shelter.
For つる, imagine a crane pulling a long string (つる) with its beak: つる -> つる, and the crane tugs the line.
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