swell
尰 centers on swelling, especially a pathological swelling or edema. The single given meaning is straightforward and does not branch into unrelated senses.
尰 combines 尢 (a person with bent or weak legs) with 重 (heavy), suggesting a condition where the legs become heavy and swollen. The exact historical development is uncertain, but the component combination fits the meaning of swelling.
A person with weak legs (尢) carrying something heavy (重) might develop swelling. Picture the legs puffing up under the weight.
For ショウ, imagine the swelling going down after a show of strength: show -> ショウ, and the heavy legs feel lighter.
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