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hashtag

American  
[hash-tag] / ˈhæʃˌtæg /

noun

  1. (on social media websites)

    1. a word or phrase preceded by a hash mark (#), used within a message to identify a keyword or topic of interest and facilitate a search for it.

      The hashtag #sandiegofire was used to help coordinate an emergency response to the fire.

    2. a hash mark used in this way.

    1. a word or phrase preceded by a hash mark (#) or by the word hashtag , used to add wit or emphasis to a spoken or written statement.

    2. a hash mark or the word hashtag used in this way, as in the sentence His goodbye was so hashtag awkward.


verb (used with or without object)

hashtagged, hashtagging
  1. to add a hashtag to (a word, topic, or message).

    Someone on Twitter just hashtagged the film festival.

hashtag British  
/ ˈhæʃˌtæɡ /

noun

  1. (on the Twitter website) a word or phrase preceded by a hash mark, used to denote the topic of a post

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What does hashtag mean? A hashtag is a word or phrase preceded by a hash mark (#), also known as a pound sign, used primarily on social media.On social media, hashtags provide users a way to search for posts related to the word or phrase in the hashtag. You can click on a hashtag to see a list of recent posts that include that keyword. (A couple of our favorites are #WordOfTheDay and #WordNerd.)To hashtag means to add a hashtag to a word, topic, or message, as in We hashtag our posts about history with #HistoryMatters so you can find them easily.Example: Use the hashtag #petthedog with a video of you petting your dog for a chance to win our contest.

Etymology

Origin of hashtag

First recorded in 2005–10; hash (mark) + tag 1 (in the sense “a label or keyword”)

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Punch's predicament sparked sympathy online, spawning a devoted Punch fanbase who began posting updates on the monkey under the hashtag #HangInTherePunch.

From Barron's

Many come with the Fight Club-inspired caption "you met me at a very Chinese time in my life", or the hashtag #newlychinese.

From BBC

An NFL spokesman confirmed to AFP that the boy was an actor, and an Instagram post seemingly from the child in question, Lincoln Fox, was hashtagged #youngbadbunny.

From Barron's

Dubbed the "crying horse" online, the depressed animal has become an internet sensation, with a related hashtag gaining more than 100 million views on social media platform Weibo.

From Barron's

His acknowledgement sparked even more excitement on Chinese social media, with many fans praising him with the hashtag "Malfoy himself is 100% hilarious".

From BBC