a.

1. 较大的；较多的
   The house needs major repairs.

   这幢房子需要大修。

2. 主要的，重要的；一流的[B]
   He is a major writer.

   他是位大作家。

3. 主修的[B]
   Her major subject is chemistry.

   她的主修科目是化学。

4. 成年的，达到法定年龄的
5. 【音】大调的，大音阶的
6. 【逻】大前提的

n.[C]

1. 成年人，已到法定年龄者
2. （常大写）陆军（或空军，海军陆战队）少校
3. （大学中的）主修科目
4. （大学专业的）主修学生
   Physics was his major.

   物理是他的主修科目。

5. 【音】大调，大音阶
   He is a mathematics major.

   他是主修数学的学生。

6. 【逻】大前提
7. 主要公司（组织、企业……等）
   MGM, Paramount, and Columbia are all majors in film industry.

   米高梅、派拉蒙和哥伦比亚都是电影业的大公司。

vi.

1. 主修[（+in）]
   Alice majors in economics.

   艾丽丝主修经济学。

adj.

1. important, serious, or significant.
   ▸greater or more important; main.
2. Music  (of a scale) having intervals of a semitone between the third and fourth, and seventh and eighth degrees. Contrasted with minor.
   ▸(of an interval) equivalent to that between the tonic and another note of a major scale, and greater by a semitone than the corresponding minor interval.
   ▸ [postpos.] (of a key) based on a major scale:

   Prelude in G Major.
3. Brit. dated (appended to a surname in public schools) indicating the elder of two brothers:
   Smith major.
4. Logic  (of a term) occurring as the predicate in the conclusion of a categorical syllogism.
   ▸(of a premise) containing the major term in a categorical syllogism.

n.

1. a rank of officer in the army and the US air force, above captain and below lieutenant colonel.
   ▸an officer in charge of a section of band instruments:

   a trumpet major.
2. Music  a major key, interval, or scale.
3. a major organization or competition.
4. N. Amer. a student's principal subject or course.
   ▸a student specializing in a specified subject:

   a math major.
5. Logic  a major term or premise.
6. Bell-ringing  a system of change-ringing using eight bells.
7. Australian Rules  a goal.

v.