Thesaurus Day
Thesaurus Day is held on January 18. It is celebrated every year on January 18th, which is the birthday of the author of Roget's Thesaurus, Peter Roget. Peter Roget was born on January 18th in 1779. This event in the second decade of the month January is annual. 
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Thesaurus comes from the Greek word for treasure. Writers often turn to a thesaurus to diversify their vocabulary and add nuance to their prose. But looking up synonyms and antonyms in a thesaurus can help anyone—writer or not—find the most vivid, incisive words to communicate thoughts and ideas.
Roget studied medicine at the University of Edinburgh and later helped found the medical school at Manchester. In 1814 he invented a “log-log” slide rule for calculating the roots and powers of numbers. A scholar and physician best known for publishing the Thesaurus of English Words and Phrases.
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