Reasonable Definition

Rational, appropriate, ordinary, just, or usual in the circumstances; "reasonable" may be used in reference to:

In most personal injury cases, for example, the "reasonable person" standard is the legal yardstick that's used to measure whether or not someone's behavior amounted to negligence. So, if a driver involved in a car accident acted as a reasonable (or "reasonably prudent" in the language of the law) person would have acted under the same set of circumstances, they might be able to avoid liability for negligence, and escape fault for the crash.