Hardwood joint with the top missing (4)

I believe the answer is:

teak

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'hardwood' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for teak that I've seen before include "Type of wood" , "Hard durable timber" , "A SE Asian hardwood" , "Hardwood tree" , "Hardwood found naturally in the Far East" .)

I've seen this clue in The Irish Independent.

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