The look of an old soldier in India (5)

I believe the answer is:

dekko

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'the look' is the definition.
(I know this)

I cannot understand how the remainder of the clue works.

(Other definitions for dekko that I've seen before include "Quick look or glance" , "Butcher's" , "Look-see" , "Quick glance (informal)" , "Shufti" .)

I've seen this clue in the Evening Standard.

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