Definition of "Major" :

noun: the principal field of study of a student at a university

"Her major is linguistics."

noun: a commissioned military officer in the United States Army or Air Force or Marines; below lieutenant colonel and above captain

noun: a university student who is studying a particular field as the principal subject

"She is a linguistics major."

noun: British statesman who was prime minister from 1990 until 1997 (born in 1943)

verb: have as one's principal field of study

"She is majoring in linguistics."

adjective: greater in number or size or amount

"A major portion (a majority) of the population."

adjective: greater in scope or effect

"A major contribution."

adjective: of full legal age

adjective: (of a scale or mode) having half steps between the third and fourth degrees and the seventh and eighth degrees

"Major scales."

adjective: of the field of academic study in which one concentrates or specializes

"His major field was mathematics."

adjective: of greater importance or stature or rank

"A major artist."

adjective: of greater seriousness or danger

"A major earthquake."

adjective: of the elder of two boys with the same family name

"Jones major."