thesaurus
nouna book that lists words in groups that have similar meanings 类义词典；义类词典；同义词词典 I couldn’t find the word in the thesaurus. 我在词典里找不到这个词。
Word Originlate 16th cent.: via Latin from Greek thēsauros ‘storehouse, treasure’. The original sense ‘dictionary or encyclopedia’ was narrowed to the current meaning by the publication of Roget's Thesaurus of English Words and Phrases (1852).