via Urban Dictionary:
The kind of activism undertaken when you “do something” about a problem by tweeting or posting links to Facebook, without any intent of ever actually doing something. Nothing more than a nonsense feelgood gesture so that one can say they “did something about” whatever trendy cause they’re pretending to care about. Usually only lasts a week or two before the cause is completely forgotten (i.e. it stops being cool to forward/retweet on the subject).
I forwarded a video about some unspeakable atrocities in a country I didn’t know existed until I watched the video. My hashtag activism is going to accomplish something!
Hashtag activism may not be the answer to our problems, but it’s a pretty good way to follow and contribute to a dialogue that may very well result in the discovery of some worthwhile solutions.
We certainly need to go further than tweeting and writing Facebook posts simply to satisfy our egos, but that doesn’t mean you have to tear down the work people are doing just because they include hashtags in their social media posts relating to a cause they genuinely care about.
I’ve written in greater detail about utilizing hashtags (and Twitter in general) as a tool for organizing here.