A free program for Android, by Erudite.
Dictionary: Word Definitions is a free and easy-to-use dictionary app that lets you look up the definitions of words. The app comes with comprehensive definitions, synonyms, antonyms, grammar, and example sentences to help you learn the most useful vocabulary most effectively. It comes with a built-in thesaurus and a vocabulary builder to help you expand your vocabulary and learn new words.
This app is a must-have for students, teachers, professionals, and anyone who wants to learn English, Spanish, French, German, Italian, Dutch, and many more.
