derelict

Derelict is an adjective meaning in a very poor condition due to neglect or disrepair, or being abandoned or deserted. Common uses include derelict buildings, vehicles, or landscapes that show visible signs of neglect and decay. As a noun, derelict can refer to a person without a home or means of support, though more often it denotes something abandoned or neglected, such as a derelict vessel or a derelict property.

The term derives from Latin dereliquitus, from derelinquere "to abandon, leave behind," via Old French and Middle English. It entered English in the late medieval period and has since developed specialized senses in maritime and planning law.

In maritime law, a derelict vessel is a ship or boat abandoned by its crew and left adrift at sea, the property of no one in particular and potentially salvageable by others. In land use and planning contexts, derelict land or buildings describe properties that have fallen into disrepair due to industrial decline or neglect and may be targeted for redevelopment or remediation. The general sense, however, connotes neglect and decay rather than intentional abandonment.

Related terms include dilapidated, decayed, and neglected, while dereliction of duty is a separate phrase referring to a failure to fulfill obligations.