A person who clicks the little red thumbs-down icon on EVERY YouTube video they watch (even videos which have no perceivable reason to be "disliked" at all), purely for the sake of doing so. It's believed that most serial dislikers suffer from a form of OCD currently unknown to science. No one knows who these people are, particularly since YouTube doesn't keep any record of who dislikes what, so research cannot be undertaken.

These people don't necessarily hate the video, but will still click "dislike" just for fun, especially if said video has no dislikes at all yet. They then delight in watching the comment section fall to ruin as a direct result of their interference, with highly intellectual and imaginative responses such as "1 person is gay", or "1 person should jump off a cliff", or "Justin Bieber made a new account to dislike this video" appearing in it.

Furthermore, the less "likes" a video has, the more devastating are the actions of the serial disliker, due to YouTube's like/dislike bar being based on the proportion between likes and dislikes, rather than on actual numbers. 1 dislike shows up as a much bigger chunk of red on the bar for a video with only 3 likes, than for one with 150. In the former case, it's much more noticeable and the commenters' outrage is slightly more justified, though in the latter case, the reactionary comments take on forms not unlike "the dislike bar is the size of Justin Bieber's penis", which is inexcusable.
Someone disliked my video of a drunk guy falling into a trashcan! Must be a serial disliker.
by Jimmy91ST July 07, 2011
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Someone that wanks way too often, the type that prefers the company of his/her hand over that of a man/woman.

The Serial Wanker can relief himself several times in one day and often does.
Terry is a serial wanker, he sits at his computer all day wanking and playing WoW
by Mesie December 30, 2010
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The guy/girl who's a complete relationship ruiner. They're pretty desperate to make it work with someone and tend to rush straight into being 'in love forever' with everyone they hook up with, only to break up a maximum of a few months later. They will never even consider that they might have caused any of their relationship problems, and will constantly be on the search for someone 'deserving' of their love and attention.
A: Did you see Tim's facebook status last night? He's only been with his girlfriend a week and he's saying he'll always love her.
B: Lol, again? The guy's a serial ex, I'll give you ten dollars it won't last more than four months.
by emilyppp February 10, 2010
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A person who likes/comments every status on your facebook. just to like them. usually a very irritating human being.
"i had like 20 notifications from that serial liker the other day!"

like facebook serial
by facebook nut August 04, 2010
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A person who likes every single post on Facebook of his/her favorite friends, no matter how stupid they are.
Damn, i was browsing Lucy's pictures on Facebook and in everyone of them there was a 'Like' by her friend Susan. She must be a serial liker.
by Stephen_Trimballs November 23, 2015
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A "Serial Poster" is typically a Facebook addict and a narcissist who compulsively will add a new post about their self every hour or less. This is for the purpose of validating their own importance to a dwindling audience who is increasingly censoring them as their enthusiasm fades away with each new self absorbed post. The Serial Poster also will have a core group 3-6 unconditional fans who will "Like" indiscriminately each post that is made regardless of it's pertinence or relevance to their own opinions.
Everyone is sick of your self absorbed posts, you have become a serial poster.
by Ben Morgasm June 22, 2014
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