A wooden smile? (4)

I believe the answer is:

beam

I believe this clue is a double definition.

'a wooden' is the first definition.
(I've seen this before)

'smile?' is the second definition.
(to beam is to smile)

(Other definitions for beam that I've seen before include "Smile widely; ray" , "Supporting piece of wood - shaft of light" , "giving a broad smile" , "Rafter - smile - width" , "Smile; piece of timber" .)

I've seen this clue in the Evening Standard.

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