English Thesaurus including synonyms and antonyms. - You can save vocabularies for your own use, and can build your own thesaurus with the bookmark words. When the bookmark look-up option is checked, it shows only your bookmarked words.- The data is stored in the app, and the operation is fast and easy to look up words. It includes some slang and informal words. More than 16,000 look-up words, and more than 40,000 synonyms and antonyms. - Three background colors are available.