hashtag¶
The use of hashtags was first proposed by American blogger and product consultant Chris Messina in a 2007 tweet.
In June 2014, hashtag was added to the Oxford English Dictionary as "a word or phrase with the symbol # in front of it, used on social media websites and apps so that you can search for all messages with the same subject".
The first published use of the term "hash tag" was in a blog post "Hash Tags = Twitter Groupings" by Stowe Boyd,19 on August 26, 2007, according to lexicographer Ben Zimmer, chair of the American Dialect Society's New Words Committee.