heads of grain, cleverness
頴 centers on a sharp, pointed tip that stands out, like the awn of a grain head. The cleverness sense extends this idea to a sharp, outstanding mind.
頴 is a variant form of 穎. The character combines 頃 (which here likely represents a grain head with awns) and 示 (possibly a simplified or variant component), with 頁 (head) on the right. The original 穎 uses 禾 (grain) on the left, emphasizing the grain head meaning. The cleverness meaning is an extended sense from the idea of a sharp, outstanding tip.
The right side 頁 means head, and the left side looks like a grain plant with a sharp awn. Picture a grain head with a pointed tip standing out prominently, like a clever idea that rises above the rest.
For エイ, imagine a grain head shaped like the letter A, which sounds like エイ. The sharp tip of the grain head is like the point of the letter A, representing cleverness.