"Circumstantial" is an adjective that refers to something that is related to the circumstances or conditions surrounding a particular situation or event. It can refer to evidence that is based on indirect or secondary factors rather than direct observation or knowledge. For example, circumstantial evidence in a criminal trial might include things like motive, opportunity, or behavior that is consistent with the commission of a crime, but is not direct proof of guilt.

The term can be used in a variety of contexts beyond legal proceedings, such as in everyday conversation. For example, someone might say that they made a decision based on circumstantial evidence, meaning that they didn't have direct proof, but they inferred something based on the available information.

Overall, "circumstantial" is a term that is used to describe something that is related to the circumstances or conditions surrounding a particular situation or event, and is often used in legal or investigative contexts to describe evidence that is indirect or inferential.