Samuel Johnson's Dictionary

“A Dictionary of the English language” is the first dictionary of English, which was written by Samuel Johnson (1709-1784, an English writer and lexicographer, born in Lichfield, England) and published on April 15, 1755. 

Johnson’s Dictionary is the most influential and the most famous lexicon in the world. The dictionary contains of 40,000 words, which are illustrated in details by 114,000 quotations. In addition, it took almost nine years to compile the dictionary. 

Sources:

-https://en.wikipedia.org/wiki/A_Dictionary_of_the_English_Language

-https://en.wikipedia.org/wiki/Samuel_Johnson

-http://www.bl.uk/learning/langlit/dic/johnson/1755johnsonsdictionary.html