The noun major has 4 senses (first 1 from tagged texts)
1. (2) major -- (a commissioned military officer in the United States Army or Air Force or Marines; below lieutenant colonel and above captain)
2. Major, John Major, John R. Major, John Roy Major -- (British statesman who was prime minister from 1990 until 1997 (born in 1943))
3. major -- (a university student who is studying a particular field as the principal subject; "she is a linguistics major")
4. major -- (the principal field of study of a student at a university; "her major is linguistics")
Overview of verb major
The verb major has 1 sense (first 1 from tagged texts)
1. (2) major -- (have as one's principal field of study; "She is majoring in linguistics")
Overview of adj major
The adj major has 8 senses (first 5 from tagged texts)
1. (39) major -- (of greater importance or stature or rank; "a major artist"; "a major role"; "major highways")
2. (26) major -- (greater in scope or effect; "a major contribution"; "a major improvement"; "a major break with tradition"; "a major misunderstanding")
3. (21) major -- (greater in number or size or amount; "a major portion (a majority) of the population"; "Ursa Major"; "a major portion of the winnings")
4. (1) major -- (of the field of academic study in which one concentrates or specializes; "his major field was mathematics")
5. (1) major -- (of a scale or mode; "major scales"; "the key of D major")
6. major -- (of greater seriousness or danger; "a major earthquake"; "a major hurricane"; "a major illness")
7. major -- (of full legal age)
8. major -- (of the elder of two boys with the same family name; "Jones major")