词义演变是所有语言共有的现象。“东”“西”原指方向，后来逐渐演变成语义丰富的复合名词“东西”。而指代物品义的“东西”是晚明时期特指来自西洋的稀奇物品、泛指抽象事物和特指人或动物语义的来源，并且“东西”在特指人、动物时附加的感情色彩源于语境。人类的主观认知和社会发展变化的客观因素都促使了“东西”的词义衍生，其词义演变过程呈现为并列式，主观化、转喻是其认知机制。

The evolution of word meaning is a common phenomenon in all languages. "East", "West" originally refer to the directions, and then gradually evolved into a semantic -rich compound noun "things". The "thing", which means the substance, refers to the rare and strange objects from the West, abstract things or the semantic meaning of a specific person or animal in the late Ming Dynasty, and the emotional color attached to the "thing" referring to the specific person and the animal comes from the context. The subjective cognition of human beings and the objective factors of social development and change promote the derivation of the meaning "things". The evolution process of word meaning is parallel, subjective and metonymy is its cognitive mechanism.