subject
n.
A principal theme or topic of a work.
The content described or depicted in a work.
Notes
A subject1 may be a person, corporation, place, topic, or period of time. It may be real or fantastic. A work may have more than one subject. - The subject2 of an artwork may be both what the work is of (what is depicted) and what the work is about (the symbolic meaning of what is depicted). For example, a photograph of a young boy working hawking newspapers on the street may be about the exploitation of child labor.