There are multiple definitions - click on the translation that matches your context.

学科

名词

full

subject

noun

Definitions of subject

a citizen of a particular country; any citizen of a particular country other than its ruler

I am a British subject.

a field of knowledge studied or taught in a school, college, or university etc

What subjects are you taking at school?

the person or thing that is being discussed, considered, or dealt with

Their story is the subject of a documentary film: The Auction House.