A FAR cry from "W"?
W being, oddly enough, the chemical symbol for Tungsten; once called Wolfram.
"The word tungsten comes from the Swedish language tung sten, which directly translates to heavy stone. Its name in Swedish is volfram, in order to distinguish it from scheelite, which is alternatively named tungsten in Swedish."
With an incandescent bulb we got thus much illumination from, say, 60-75 Watts We then got a similar amount of light from , in this case, 11W.
I've just seen the Bathroom brighter than it has ever been courtesy of a few Watts of L.E.D.