Greek hero's contribution to the RN (4)

I believe the answer is:

ajax

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'greek hero's' is the definition.
(I've seen this in another clue)

I cannot understand how the rest of the clue works.

(Other definitions for ajax that I've seen before include "Mythical Greek hero, who fought against Troy" , "old privy" , "Strong Gr. hero (Iliad)" , "Legendary warrior" , "Son of Telamon, hero of Trojan War" .)

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