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2.
tremendously, more than you expected, allot.
"I hoped you get paid majorly"
by Nzinga K October 09, 2006
 
1.
(adverb) very, very, very
That movie was majorly stupid.
by Anonymous January 14, 2003
 
3.
1. adj. Very much, or intensly so

2. A LEGIT WORD (NOT SLANG, as opposed to legit), THOUGH A REAL DICTIONARY WOULD LIKE TO DISAGREE
1. Wow. That concert last night was majorly cool. I loved the pyro!

2. Avery: "I just found out that majorly isn't a real word"

Taylor: "WHAT"

Avery: "I KNOW. IT'S 'SLANG'. WHAT THE HELL"
by screw you, webster July 18, 2009
 
4.
majorly is what you get when you mumble and slur "major league". So, I am "major league" annoyed = I am "majorly" annoyed.
"He was majorly upset."
by david June 28, 2004