One who looks, but doesn't sound, a bit of a lout (3)

I believe the answer is:

lou

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'one who looks but doesn't sound a bit of a lout' is the definition.
The definition suggests a singular noun which matches the answer.

This is the entire clue.

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(Other definitions for lou that I've seen before include "-- Costello, Abbott's partner" , "--- Costello, US comic" , "-- Reed, singer" , "man" , "-- Reed, rock musician" .)

I've seen this clue in the Evening Standard.

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