Scrabble?! HASHTAG

Definitions of HASHTAG in various dictionaries:

A hashtag is a type of metadata tag used on social networks such as Twitter and other microblogging services, allowing users to apply dynamic, user-generated tagging which makes it possible for others to easily find messages with a specific theme or content; it allows easy, informal markup of folk taxonomy without need of any formal taxonomy or markup language. Users create and use hashtags by placing the number sign or pound sign # (also known as the hash character) in front of a string of alphanumeric characters, usually a word or unspaced phrase, in or at the end of a message. The hashtag may contain letters, digits, and underscores. Searching for that hashtag will yield each message that has been tagged with it. A hashtag archive is consequently collected into a single stream under the same hashtag. For example, on the photo-sharing service Instagram, the hashtag #bluesky allows users to find all the posts that have been tagged using that hashtag. Because of its widespread use, ha