甲骨文Oracle Bone Inscription:
贝 is an obvious Pictogram from its formation of Oracle Bone Inscription and Bronze character, looking like a shellfish, an aquatic animal that has a shell or shell-like exoskeleton. As a result of its rarity in ancient China, the shell of shellfish used to be taken as a medium of exchange as well as an ornament of luxury exclusively for ruling class or the nobility. 贝 has become one of the frequently used radicals in modern Chinese, and characters containing a component of 贝 are usually associated with wealth, riches, something precious and valuable, or the practice of trading goods.
本义Original meaning: 海贝，贝壳 shellfish, shell
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