major has 3 distinct synonyms spread across 1 of its 13 senses. Each sense below keeps its own list, because a synonym belongs to a meaning and not to a word: swapping one sense's substitute into another sense's sentence is how a thesaurus makes writing worse. Its one recorded opposite is minor.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
of greater importance or stature or rank
“a major artist”
greater in scope or effect
“a major contribution”
greater in number or size or amount
“a major portion (a majority) of the population”
1 of the 13 recorded senses carries no synonym, antonym or related term, so it is not shown above. Every sense, with its definition and examples, is on the full entry for major.
Synonyms, antonyms and the broader and narrower relations for major come from Princeton University’s WordNet. Full sources and licences.
of the field of academic study in which one concentrates or specializes
“his major field was mathematics”
(of a scale or mode) having half steps between the third and fourth degrees and the seventh and eighth degrees
“major scales”
of greater seriousness or danger
“a major earthquake”
of full legal age
a commissioned military officer in the United States Army or Air Force or Marines; below lieutenant colonel and above captain
British statesman who was prime minister from 1990 until 1997 (born in 1943)
a university student who is studying a particular field as the principal subject
“she is a linguistics major”
the principal field of study of a student at a university
“her major is linguistics”
have as one's principal field of study
“She is majoring in linguistics”