Synonyms of 'lexicon'
A dictionary is a book in which the words and phrases of a language are listed alphabetically, together with their meanings or their translations in another language.
If you don't know what it means, look it up in the dictionary.
Thesaurus for lexicon from the Collins English Thesaurus
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.