A more thorough explanation:

Definition: A walker is a person who inspects a specific area of land, usually a forest, to ensure that everything is in order.

Example: In medieval times, a walker was responsible for checking the forest for any illegal activities such as poaching or logging without permission.

Explanation: The example illustrates how a walker was responsible for inspecting a specific area of land, in this case, a forest, to ensure that everything was in order. The walker's duties included checking for any illegal activities such as poaching or logging without permission. This ensured that the forest was well-maintained and protected from any harm.