Merriam-Webster Dictionary API

Merriam-Webster has been producing language information—including dictionaries, thesauri, and translation materials—for over 150 years. The Merriam-Webster collection of APIs provide developer access to a variety of the company’s most prominent reference works. Free access is provided to non-commercial websites and applications. Free access is limited to two reference works with a maximum of 1000 queries a day per reference work. Full access is available for commercial use.