April 15, 1755, Samuel Johnson published his A Dictionary of the English Language. 

Ne’twork. n.s. [net and work.] Any thing reticulated or decussated, at equal distances, with interstices between the intersections.

 
Samuel Johnson 1709-1784
Part off the Eminent Britons (Europa C.E.P.T. 2009) series
Issued August 10, 2008 by Royal Mail
Designed Together Design Ltd. using a portrait by Joshua Reynolds

Johnson spent 8 years compiling his 2-volume dictionary. Although not financially rewarding, the dictionary was greeted with great acclaim in his lifetime and established his reputation.    

The Dictionary was an extraordinary achievement. Between 1747 – when he dedicated his Plan of an English Dictionary to the indifferent Lord Chesterfield – and 1755, Johnson, working almost entirely alone, compiled not only etymologies and definitions for his two volumes but also a huge number of illustrative quotations from the best models of English prose and poetry. His work stands as the foundation upon which all modern dictionaries have been built and is all the more remarkable when you know that it was completed amidst poverty, neglect, loneliness and sorry (his wife, “Tetty”, died in 1752), and in a vigorous but often failing effort to combat indolence and despair. 
Eighteenth Century Poetry & Prose, third edition, Louis I. Bredvold, Alan D. Mckillop and Lois Whitney p. 695.

Johnson’s Dictionary Online (johnsonsdictionaryonline.com) is a lot of fun poking around. They have digitised the entire dictionary so you can search for words and … well enjoy.