Abstract:Cognitive linguists believe that metaphor and metonymy have an important effect on the extending of meaning. The present paper analyzes how the two cognitive mechanisms help to extend the meanings of water via the collected data. Studies have shown that: the meaning of word water has undergone from the basic meaning to the conventional meaning in the course of expansion, which is the result of cognitive model of metaphor and metonymy. In the end, the article does a cross-cultural research on the category of polysemous word meaning and summarizes the characteristic of polysemous meaning construction. On the one hand, no matter what kind of language, semantic category is expanding by virtue of metaphor and metonymy, so the semantic category has the nature of cognitive commonness. On the other hand, it is the same that people cognize things from different angles due to cultural differences though the expanding mechanism of semantic category. Thus the expansions of specific paths are differing that we can see the reflection of cultural identity on semantic category.

Key words: polysemous word; cognition; metaphor; metonymy; culture

摘要:认知语言学认为隐喻和转喻对词义延伸起了很重要作用。本文通过收集并分析汉英语言中包含“水”和“water”的表达，从跨语言的角度来考察隐喻和转喻这两种认知机制的作用。研究表明：“水”一词词义经历了从基本词义到各常规词义扩大的过程，这是认知模式隐喻和转喻作用下的结果。

　　　文章最后对多义词意义范畴进行了跨文化研究,总结了多义词意义构建的特点。一方面,无论是何种语言,语义范畴都是凭借隐喻和转喻而拓展的,因此语义范畴具有认知共性。另一方面,虽然语义范畴的拓展机制相同,但是由于文化的不同,人们对事物的认知角度不同,因此拓展意义的具体路径不同,导致语义范畴体现出文化个性。

关键词：一词多义；认知；隐喻；转喻；文化