Wood in Skelmersdale (3)
I believe the answer is:
elm
'wood' is the definition.
(elm is a type of tree)
'in skelmersdale' is the wordplay.
'in' says the answer is hidden in the clue.
'ELM' can be found hidden inside 'skelmersdale'.
(Other definitions for elm that I've seen before include "Victim of fungus" , "wood used in pelmets" , "Tree of the genus Ulmus" , "Timber tree" , "Gray's rugged tree (Elegy)" .)