1 definition by Mr. Walrus from Walrus Land

The bad sickness you get when listening to Justin Bieber. *Only some get it* It may spread around. THERE IS NO CURE TO BIEBER FEVER YET.
Example of Bieber Fever:

Justin Bieber: ♫Baby, baby baby ohhhh♪

You: OGMOGMOMGMGOMG LET'S FAN GIRL JUSTIN BIEBER OMG I LOVE HIM HE IS SO CUTE HIS HAIR IS ADORABLE OMG HIS SMILE... OH HE'S COMING TO OUR TOWN LET'S SEE HIS CONCERT WOWOWOWOWW MY ROOM IS PLAIN, I'M GONNA COVER MY WALLS WITH JB POSTERS!!!!!!!!!

Me: smh
Get the Bieber Fever mug.