Dope the dog (4)

I believe the answer is:

mutt

This clue is a double definition.

'dope' is the first definition.
(thesaurus)

'the dog' is the second definition.
(mutt is a kind of dog)

(Other definitions for mutt that I've seen before include "Mongrel dog - foolish person" , "Mongrel - fool" , "Chump" , "far from best in show?" , "Setter perhaps" .)

I've seen this clue in the Evening Standard.

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