light show vs showing

light show and showing both are nouns.

Word	Noun	Adjective	Verb	Adverb
light show	Yes	No	No	No
showing	Yes	No	No	No

As nouns, showing is a hypernym of light show; that is, showing is a word with a broader meaning than light show:

Other hypernyms of light show include display, exhibit.

light show (noun)	showing (noun)
a display of colored lights moving in shifting patterns	something shown to the public
	the display of a motion picture