Crossword Genius

Highlighter-colored (4)

Ross

I believe the answer is:

neon

(Other definitions for neon that I've seen before include "Form of lighting" , "None (anag.)" , "Gas used in fluorescent lamps" , "One of the six inert gasses" , "Colourless gas, used in lighting" .)

I've seen this clue in The New York Times.
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