What legal term describes the use of land by someone other than the landowner openly, hostly, and continuously for a period?

The appropriate legal term that describes the use of land by someone other than the landowner in an open, hostile, and continuous manner for a certain period is known as adverse possession. This concept allows an individual to gain legal ownership of a piece of property if they occupy it under specific conditions, which typically include maintaining open possession of the land, using it without the permission of the original owner (hostile), and doing so continuously for a legally defined duration.

Adverse possession operates under the principle that the true owner has neglected to assert their rights over time. If someone can demonstrate that they have met these conditions, they may potentially claim the title to the property. This concept is based on the ideas of utility, fairness, and promoting the productive use of land.

Although prescription also involves the use of another's land, it is generally associated with acquiring an easement rather than ownership, thereby making it distinct from adverse possession. An easement appurtenant involves a property right that benefits a specific parcel of land, while an implied grant refers to a situation where property rights might be granted implicitly due to circumstances without a formal deed. Hence, adverse possession is the most accurate term for the scenario of occupation and use of land as described in the question.