Left: movement 辶, right: common, various 庶 (In a building 广 cooking pot 廿 on the fire 灬 is just common) - Here: 廿 as the horns of animals, cf.: leather 革
Mnemonic
(No free-range livestock): We have the stable/hutch 广 for the animals (horns 廿 and 4 legs 灬) such that their movement is: intercepted / interrupted.
A horned 廿 animal seen from above with a backbone 丨 and broad hips 一 has a skin 囗 of leather around its torso. - This radical 皮 also stands for leather.
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