Eager to wail (4)

I believe the answer is:

keen

This clue is a double definition.

'eager' is the first definition.
(I've seen this in another clue)

'to wail' is the second definition.
(I've seen this in another clue)

(Other definitions for keen that I've seen before include "Diligent" , "Fervent" , "display grief" , "Penetrating; ardent" , "Avid, enthusiastic" .)

I've seen this clue in The Everyman puzzle in The Observer.

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