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 really 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 in the remaining 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" .)