In a business sense, a piece of property that is totally inaccessible via public thoroughfare, except through an adjacent lot. A vacant lot that is located behind a strip mall and can only be reached by walking through the mall qualifies as this type of lot. Landlocked property is "locked up" all around by other property.
Landlocked property is generally worth less than other properties, due to its inaccessibility. As the old saying goes in real estate, "location, location, location." This disadvantage makes these properties harder to sell in many instances.
Investment dictionary. Academic. 2012.