Dictionary by Merriam-Webster: America's most-trusted online dictionary

REFERENCE
Merriam Webster has been synonymous with the word dictionary for over 150 years. While its been the most trusted provider of language information in print (like the Merriam Webster’s Collegiate Dictionary), it’s also currently a reference portal for language online as well. The Merriam Webster dictionary has over 40 million visitors monthly.
Site content is also supported by the largest and brightest team of professional dictionary editors and writers in the United States, the brand’s home base.