The historic Hessians' game (5)

I believe the answer is:

chess

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'game' is the definition.
(board game)

'the historic hessians'' is the wordplay.
'CHESS' is hidden within the letters.
But, I am not sure how the hidden word is indicated.

Can you help me to learn more?

(Other definitions for chess that I've seen before include "Game involving mates" , "that has over thirty men on board" , "Ancient war game whose name may have derived for the Persian for 'king'" , "form of battle" , "Pure-skill board game" .)

I've seen this clue in the Evening Standard.

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