adjective Likely to be affected by or to experience something; liable.
a country subject to extreme heat
adjective Conditional upon something; used with to.
The local board sets local policy, subject to approval from the State Board.
adjective Placed or situated under; lying below, or in a lower situation.
adjective Placed under the power of another; owing allegiance to a particular sovereign or state.
noun The noun, pronoun or noun phrase about whom the statement is made. In active clauses with verbs denoting an action, the subject is the actor. In clauses in the passive voice the subject is the target of the action.
In the active sentence ‘The cat ate the mouse’, ‘the cat’ is the subject and ‘the mouse’ is the object.
noun By extension: an actor or agent; one who takes action.
the subjects and objects of power
noun The main topic of a paper, work of art, discussion, field of study, etc.