Instrument costing nothing no good? Return it! (5)

I believe the answer is:

sitar

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'instrument' is the definition.
(musical instrument)

I don't understand the rest of the clue.

(Other definitions for sitar that I've seen before include "Indian string instrument" , "It takes pluck" , "Hindu stringed instrument" , "Large Indian lute" , "Stringed instrument of the subcontinent" .)

I've seen this clue in The Times.

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