What term describes the reasonable space above a parcel of land?

The term that describes the reasonable space above a parcel of land is "airspace." In real estate, this concept refers to the vertical space above the land surface where property rights can be claimed and utilized, subject to certain regulations and restrictions.

Airspace is an essential component of property ownership since it governs various activities, such as construction and installation of structures like towers, antennas, and even signs. The rights to this space can impact zoning laws and development regulations, as landowners cannot simply build as high as they wish without consideration of these factors.

The other terms provided do not accurately capture this specific concept. "Land Boundaries" refer to the physical lines that delineate a property on the ground. "Parcel Space" is not a standard real estate term and does not convey the idea of vertical space above land. "Property Limits" could imply either physical boundaries, including both land and airspace, but does not specifically denote the airspace above a property in a legal or practical sense. Therefore, airspace is the most precise term to use in this scenario.