Element with symbol W (8)
I believe the answer is:
tungsten
'element with symbol w' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for tungsten that I've seen before include "Wolfram" , "Element used in steels" , "Hard metal used in light bulb filaments" , "Metallic element, W" , "Chemical element, symbol W" .)