#_w
Top Voted Definition for #_w
_w is affixed to the end of a normal hashtag to indicate the tweet is a witness account of an event - i.e. somebody "on the ground". Example: Japan Earthquake - the trending hashtag was #jpquake. An eye witness account would have had the hashtag #jpquake_w The _w is known as a Hashtag Affix. See HashtagAffix.com for more details
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