derelict

adjective

definition 1: failing to fulfill one’s responsibilities or obligations; remiss.
examples: He was ashamed, knowing how derelict he’d been in visiting his mother at the care home.
The judge found the young woman derelict in the care of her children.

definition 2: abandoned, usu. because of failure to function.
example: A derelict automobile was left at the side of the road.

noun

definition 1: anything that has been abandoned by the owner, esp. a ship.

definition 2: someone without a home or means of support; vagrant.

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