Female deadlier than the male (6)

I believe the answer is:

amazon

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'female' is the definition.
(I know that amazon is a type of adult female)

I cannot understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for amazon that I've seen before include "Warlike female" , "Flower" , "S. America's longest river" , "Mythic woman warrior" , "Strong, aggressive woman" .)

I've seen this clue in the Evening Standard.

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