the world > action or operation > inaction > idleness, lack of occupation or activity > unoccupied [phrase] (4)
(In later use perhaps influenced by sense 9d.) out of play: not in operation or effect, inactive; (formerly also) †unoccupied, out of employment…
Available; unoccupied. In later use: spec. (of an actor or performer) out of work; available for employment.
in dry dock (figurative): inactive, unemployed; in quarantine; in hospital. colloquial.