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16.
Awesome paladin tank on the horde side of the Bronzebeard EU server.

"Man that Flatlíne is the shizzle"

Known for his wit, handsome good cow looks, and ability to abuse bad dps.
Omg its Flatlíne. Watch your threat before he pwns you
by angryqqer August 17, 2011
 
1.
verb: to "kill" someone - literally or figuratively
"if you ever bring up my ex's name around my current squeeze again.....so help me dude, I WILL flatline you!"

"I heard one of the perps got flatlined by the cops at that liquor store robbery last night."
by Hipster November 18, 2006
 
2.
Dead. Refers to a heart monitor.
The gang flatlined that noisy bitch.
by Muze April 20, 2006
 
3.
brain dead, stupid , celebrally challenged, Stems from the flat line response of a dead person from ECG machine.
Chris luton is a flatliner
by Socrates September 15, 2003
 
4.

1. dead(from the flat line on the heart monitor of the patient when there is no heart activity, meaning that they have died or their heart has stopped)

2. to die
Don't let him flatline now.
by The Return of Light Joker February 03, 2009
 
5.
Adjective.
(1) Describing anything that is uneventful, monotonous, boring, very ordinary.
(2) A pointless encounter. The basics of living with nothing more to excite/stimulate the mind and/or body.
A: Yo how was that party you were just at?
B: Dude, it fucking sucked, no beer, no fights, no girls, that party was flatline.
by Chachh August 22, 2006
 
6.
1. To be dead, refering to how ECG machines' little green line goes flat when someone is dead.
2. To kill someone, literally or figuartively.
3. To be retarded, metally challenged, stupid, dimwit, and/or dumb.
4. A game where people choke themselves to get the feeling equivalent to be high. Therefore, legally high. Also known at the Choking Game and Space Monkey(s).
1. "Doc, the patient hass flatlined!"
2. a) The marine flatlined the Iraqi terrorist.
b) "I'll flatline you if you tell my mom I got a 46 on my math test!"
3. "Did you just figure out that water is wet? Wow Flatline, you're a few fries short of a Happy Meal.
4. A lot of kids accidently kill themselves trying to get high while playing Flatline
by Carrera's Wedge April 28, 2007
 
7.
A monotonous, expressionless person, lacking any enthusiasm or emotion. The term comes from hospital lingo, where a patient is said to flatline when a continuous straight line is displayed on their heart monitor, indicating death.
"...as excited as that flatline can get. I had to remind him twice to keep breathing."
by Der Golem February 07, 2010