|Cartoon debut||"D.W.'s Name Game"|
The thesaurus is a dinosaur who is very good with words.
He spends most of his time organizing words in the library's reference section, but there are so many that he still has a lot to go. He appears in D.W.'s dream. After testing her worthiness, he told her the perfect name to call Arthur.
- He is named after a thesaurus, a book that lists words, similar meaning words, and opposites.