Second-hand, unsteady, regularly failing (4)

I believe the answer is:

used

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'second-hand' is the definition.
(I've seen this in another clue)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for used that I've seen before include "was milking" , "Availed oneself of" , "Previously owned by another" , "Was treating" , "cast off" .)

I've seen this clue in The Everyman puzzle in The Observer.

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