1.

a phrase intended to make someone feel even worse about their current misfortune, by telling them to savour the emotional "burn" which they they are already feeling.

similar to the phrase sucked in

2.

more common usage:

when your muscles generate a burning feeling during intense exercise

For example:

1.

Person 1: I am getting audited by the tax man
Person 2: Feel the burn!

Person 1: I just had a car accident and I forgot to pay my insurance!
Person 2: Feel the burn!

The phrase can be enhanced with the double entendre

Person 1: That girl gave me genital warts
Person 2: Feel the buuurrrrrrn!

Person 1: I burnt myself on the stove
Person 2: Feel the buuuuuurrrrrrrrrrrrrn!

Burn is enhanced the longer you hold the 'ur' sound.

Buuuuuuuuuurrrrrrrrrrrrrrrrn!

2.

Personal Trainer: Not until you are feeling the burn can you call that jogging you fatty.
by Dan55 November 13, 2007
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when some pain in the ass thing is a life workout that is sooooooooooo getting you laid
YOU: I have to go take my mother-in-law to the airport.

YOUR BUDDY: Feel the burn, dude.
by mattyfoureyes December 18, 2010
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(1)-Interjection- Used when someone is running around on fire while you hold the godly flamethrower.
"Feel the burn kid?"
"ITS ON MY PANTS!!!! AHHHHH!"
by Rage April 24, 2003
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