Thesaurus

The Thesaurus is a dinosaur that 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 has a lot to go. He appears in D.W.'s Name Game in D.W.'s dream. After testing her worthiness, he told her the perfect name to call Arthur. He must be very good at words because Arthur melted after hearing it.

Trivia
He is named after a thesaurus, a book that lists words, similar meaning words, and opposites.