しゅご主語shugo
1.
A component of a sentence that indicates what is performing an action or being described, often found in phrases such as "what is doing what" or "what is in what state," but may not necessarily be stated in every sentence in Japanese.
2.
In logical terms, the entity or topic that is being referred to in a statement or proposition, typically represented by a specific term within the sentence structure.
Example:
英語の文構造は大抵、主語、動詞、目的語／補語だ。