Strut for instance extended across wood (6)
I believe the answer is:
sashay
'strut' is the definition.
(I know that strut can be written as sashay)
'for instance extended across wood' is the wordplay.
I cannot quite see how this works, but
'wood' could be 'ash' (wood from an ash tree) and 'ash' is found within the answer.
'for instance' could be 'say' (both can be used to introduce an example) and 'say' is found within the leftover letters.
No letters remain.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for sashay that I've seen before include "Excursion" , "Walk glidingly" , "move with flamboyance" , "Walk showily" , "Walk exaggeratedly" .)