The look of an old Indian army man? (5)

I believe the answer is:

dekko

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'the look' is the definition.
(dekko is a kind of look)

I don't understand how the remainder of the clue works.

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

I've seen this clue in the Evening Standard.

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