A major musical instrument (4)

I believe the answer is:

pipe

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'musical instrument' is the definition.
(pipe is a kind of musical instrument)

I cannot understand how the rest of the clue works.

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(Other definitions for pipe that I've seen before include "It can be played or smoked" , "Tropical fruit" , "Main provider" , "Tube with bowl for smoking tobacco" , "Tube carrying liquid or gas" .)

I've seen this clue in the Evening Standard.

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