Free to be angry (4)

I believe the answer is:

wild

I believe this clue is a double definition.

'free' is the first definition.
(thesaurus)

'angry' is the second definition.
('wild' can be a synonym of 'angry')

'to be' acts as a link.

(Other definitions for wild that I've seen before include "Not tamed" , "Impulsive" , "Unrestrained" , "Born Free?" , "Feral - crazy" .)

I've seen this clue in the Evening Standard.

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