1. Laughing at somebodys complete stupidity in an online setting such as a forum or youtube.

2. Can also be said in an effort to make somebody look foolish.

3. This may sometimes be said to denote confusion with no bad intentions intended.

Also it is intentionally spelled incorrectly to annoy people of the Grammar Nazi Disposition.
Somebody posts something nonsensical or foolish on a forum, and the first reply is 'lul wut?'

After a big looong rant on the forum about internet peoples spelling someone reply's lul wut? to infuriate the OP (original poster)

A friend text you an incoherent message and you reply with 'lul wut?'
by Irishlooser18 January 8, 2012
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Hilarious internet misspelling of the phrase "wait, what"
Wate wut, are you sure about this?
by Photon October 6, 2003
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A way to respond in a annoying way to a question
"hey did you do the home work"
"wut B"

"no seriously did you"
"Wut B"

"nvm Ill go ask billy"
"Wut B"
by Bryant Canales April 3, 2008
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When you’re on a discord call with your main homies and one of them looks up their names on UrbanDictionary and you learn you can make a word on the website
Give me a sound.”
“Blep wut?”
by The Lord of the Gay June 7, 2021
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Word that became very popular on the World of Warcraft forums on April Fool's day 2007. During the course of the day, the Blizzard forums were changed so that each normal poster had blue text and an animated icon, which is normally what Blizzard posters look like. To go along with this, each Blizzard poster was listed as a player, with normal white text, and a troll for an icon, signifying they were forum trolls. The staff posted sporadically all day in threads, trolling. One of the expressions used in most of the one-line replies was "lol wut?" After this, it became very popular on the forums for the next few weeks.
Player A says: I think that Warlocks should be nerfed!
Tseric says: Lol wut?
Player B says: Lol wut?
Player C saysL: Lol wut?
by Vidus April 16, 2007
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Literally meaning,
"Laugh out loud, what?"
Something you might say when someone says something awkward or something that makes no sense, but is still funny in a certain way. Often used in IMs and forums, this is, of course, a retardation of a phrase.
Nerd 1: oh sry dood, i wuz just attackd by super flying ninja monkey mutants.

Nerd 2: LOL WUT???
by MagicsDevil March 15, 2009
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Used in a "o rly" way to suggest that what they said was

nonsense
spam
or obvious.

Can also be used in a taunting "I can't hear you!" way, but is generally more effective.
Person 1: STFU, NEWB!
Person 2: Lulz wut?
by Ookami Raito September 20, 2007
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