Definitions
A word or phrase marked with a hash sign to group online posts.
Word origin
From earlier hash tag, from hash (sign) + tag. The hash sign # was initially proposed as tag hash by Chris Messina to create groups on Twitter, modeled after the IRC channel prefix. First published use as hash tag by Stowe Boyd in 2007.
Used in a sentence
“I support the hash tag convention: http://tinyurl.com/2qttlb #hashtag #factoryjoe #twitter”
“You can also search for a hashtag by typing a topic (without the #) in the search box and clicking Search.”
“While hashtags aren't formally part of Twitter, some clients, such as Tweetdeck, will persist hashtags across replies to create a sort of message threading.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer1 curated clues
01“Social media marker”7 letters
Not quite right?
"Search similar patterns."
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