prescriptive easement

Definition from Nolo’s Plain-English Law Dictionary

A right to use property, acquired by open and obvious use, without the owner's permission, over a minimum period of time established by state law. For example, if hikers have been using a trail through your backyard for ten years and you've never complained, they probably have an easement by prescription through your yard to the trail.

Definition provided by Nolo’s Plain-English Law Dictionary.