Long flat piece of timber (5)
I believe the answer is:
plank
(Other definitions for plank that I've seen before include "Building timber" , "Long piece of wood" , "Prepared piece of wood" , "Wooden board" , "Long piece of timber" .)
I believe the answer is:
plank
(Other definitions for plank that I've seen before include "Building timber" , "Long piece of wood" , "Prepared piece of wood" , "Wooden board" , "Long piece of timber" .)