The subject case refers to the grammatical form of a noun, pronoun, or adjective, which functions as the subject of a sentence. Its antonyms, on the other hand, are words that indicate the opposite meaning or functional position of the subject case. They include the object case, which refers to the grammatical form of a noun, pronoun, or adjective that functions as the object of a sentence, and the possessive case, which refers to the grammatical form that shows ownership or possession of something. Other antonyms of the subject case include the verb, which indicates an action or state, and the predicate, which contains a verb and describes the subject.