An area of knowledge

In music, the first melodic fragment of a fugue

The focus of a field of study

Research subject, an organism that is observed for purposes of research

An element in the method of modeling information called Resource Description Framework

British subject, a term concerning British nationality

Subject (grammar), one of two main constituents of a sentence

Subject (philosophy), a being which has experiences or a relationship with another entity or "object"

Knowledge summary and related information.

An area of interest, also called a "topic". See Lists of topics and Lists of basic topics.

The focus of a course of study or of a class at school

Federal subject, the basic subdivision of the Russian Federation. Each federal subject is a constituent region of the federation.