major
US /ˈmeɪ.dʒɚ/
UK /ˈmeɪ.dʒɚ/

1.
1.
an officer of middle rank in the armed forces, above captain and below lieutenant colonel
:
•
The Major gave orders to the troops.
•
She was promoted to Major last year.
2.
a student's main field of study
:
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Her major is computer science.
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What's your major?
1.
to specialize in a particular subject at a college or university
:
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She decided to major in history.
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He plans to major in economics.