Rod's sorry – as Spooner told panel (8)
I believe the answer is:
wainscot
'panel' is the definition.
(wainscot is a kind of panel)
'rod's sorry as spooner told' is the wordplay.
I cannot really understand how this works, but
'as' could be 'in' (I've seen this in other clues) and 'in' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for wainscot that I've seen before include "Panelling on lower part of interior walls" , "Boarding" , "Old oak" , "Lining of a wood-panelled wall" , "Wooden board at the bottom of a wall" .)