grazing fire vs firing

grazing fire and firing both are nouns.

Word	Noun	Adjective	Verb	Adverb
grazing fire	Yes	No	No	No
firing	Yes	No	No	No

As nouns, firing is a hypernym of grazing fire; that is, firing is a word with a broader meaning than grazing fire:

grazing fire: fire approximately parallel to the ground; the center of the cone of fire does rise above 1 meter from the ground
firing: the act of firing weapons or artillery at an enemy

Other hypernyms of grazing fire include fire.

grazing fire (noun)	firing (noun)
fire approximately parallel to the ground; the center of the cone of fire does rise above 1 meter from the ground	the act of setting something on fire
	the termination of someone's employment (leaving them free to depart)
	the act of discharging a gun
	the act of firing weapons or artillery at an enemy