Which of the following best describes the act of defining something correctly as it fits legal standards?

The term 'proper' refers specifically to something that aligns with established standards or rules, particularly in a legal context. When something is defined as proper, it indicates that it adheres to the regulations, laws, or norms within a given framework. This is crucial in legal settings where precise definitions can significantly impact the interpretation and application of the law.

In contrast, the other terms listed do not carry the same connotation of adherence to standards. 'Property' typically refers to ownership or a physical entity. 'Relevance' pertains to the importance or significance of information in a particular context, while 'quality' generally describes the standard of something, but does not specifically address legal compliance. Thus, 'proper' is the best fit when discussing definitions in relation to legal standards.