1 N-SING （某一学科、个人或群体的）全部词汇 The lexicon of a particular subject is all the terms associated with it. The lexicon of a person or group is all the words they commonly use. （某一学科、个人或群体的）全部词汇

2 N-COUNT （某一语言或学科的）词汇表 A lexicon is an alphabetical list of the words in a language or the words associated with a particular subject. （某一语言或学科的）词汇表

3 N-COUNT （尤指希腊语、希伯来语等古老语言的）词典，字典 A lexicon is a dictionary, especially of a very old language such as Greek or Hebrew. （尤指希腊语、希伯来语等古老语言的）词典，字典 [old-fashioned]