Smile; timber (4)
I believe the answer is:
beam
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">smile</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(to beam is to smile)</span><br/ ><br/ >'<span class="explanation-format__original">timber</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I have seen 'Sturdy timber ' mean 'beam' so perhaps 'timber' could also mean 'beam')</span><br/ ><br/ ></span>
(Other definitions for beam that I've seen before include "Ray of light or a large smile" , "Sturdy timber" , "A supportive" , "Smile, light shaft" , "Rafter - smile - width" .)