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1. Hashtag
If you have been on Twitter, you may have seen a "hashtag." To put it simply, a hash tag is simply a way for people to search for tweets that have a common topic and to begin a conversation. For example, if you search on #LOST (or #Lost or #lost, because it's not case-sensitive), you'll get a list of tweets related to the TV show. What you won't get are tweets that say "I lost my wallet yesterday" because "lost" isn't preceded by the hash tag.

Hashtags believed to have originated on Twitter but, interestingly enough, it is not a Twitter function. Some believe it began when the broken plane luckily landed in the Hudson River in early 2009, some Twitter user wrote a post and added #flight1549 to it. I have no idea who this person was, but somebody else would have read it and when he posted something about the incident, added #flight1549 to HIS tweet. For something like this, where tweets would have been flying fast and furiously, it wouldn't have taken long for this hash tag to go viral and suddenly thousands of people posting about it would have added it to their tweets as well. Then, if you wanted info on the situation, you could do a search on "#flight1549" and see everything that people had written about it.
Take this ashtag for example: #worstjobeverhad. This Hash tag would compel many others to share the worst jobs they've ever had, thus contributing to a fun conversation. It can be used for specific searches or individual twitters that begin them for their followers.

For further clarification on hashtags and for everything for everything else Twitter please visit: TwitterFanZone.com
2. Hashtag
Hashtag-Noun. Spawned from the ever powerful Twitter Machine, this symbol (#) has become a new way to add a thought, or some up the thought of, a sentence, giving it more clarity, and often, more wit. Most commonly found in tweets, FB status, and comments (in that order)
"Just eat an entire sleeve of oreos cookies in 8 mins #highlife"

"Wegmans didnt have MY kind of Organic Milk, so i had to by that silk shit instead #whitegirlproblems"

"Going car shopping today because my last car caught on FIRE #nbd

#=Hashtag
3. Hashtag
When hash smokers get a quote on the price of the amount of hash they're buying from the dealer. it is written on a little tag, much like a price tag and is found at the pickup spot.
yo man I get the hashtag lastnight behind the BigD. this mofo is asking 200 big ones for a teenth
4. Hashtag
A scent that the Tag Fragrance Company(A division of Proctor & Gamble) attempted to market to the "stoners" or "potheads" in the western part of the United States and Southwest Canada. The market research focus groups took place in three cities, Seattle, San Francisco, and British Columbia. It seemed to be going well during the initial phases of the tests. Everybody loved how it smelled "earthy and sweet" at first, but did not like however, that after a few minutes, there was a "noticeable, underlying funk that just wouldn't wash off or go away."(Much like the members of these groups and the couches that they happened to be staying on at the time. Respectively.) They did try to overcome that hurdle by adding patchouli oil to the concoction, but found it only temporarily masked the stench. The Tag Fragrance Company and Proctor & Gamble, at the advisement of their corporate lawyers, ultimately decided against the release of Hashtag when the test subjects were caught deliberately concentrating, then inhaling the contents of the spray cans out of giant balloons in an effort to "catch a free buzz".
"Uh, dude..... If they sell hashtag at the co-op or natural market you go to, let me know and... uh, what was i saying bro? Oh yea...uh.... let me know if they will trade for like, these hummus burritos I got, or these hacky sacks my friend Rainbow made out hemp seeds and old dreadlocks. Hey dude wanna get a hack circle goin? Wait... oh yea, if they have it, just let me know so I can go steal some.
5. Hashtag
Recent baby name
Hi my name is Hashtag I'm a potential serial killer.
6. hashtag
Its a tag used to talk about an especif subject on twitter.
Once all the users use it, it gets a lot easier to search subjects at the http://search.twitter.com/
#bailout I cant believe they're refusing the deal.

In this case, the hashtag is #bailout.
7. hashtag
The game played by crack babies when they grow up to become old enough to leave the house (usually around 3 years old.)
Let's go play hashtag over by the poppies.
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