shooting vs headshot

shooting and headshot both are nouns.

Word	Noun	Adjective	Verb	Adverb
shooting	Yes	No	No	No
headshot	Yes	No	No	No

As nouns, headshot is a hyponym of shooting; that is, headshot is a word with a more specific, narrower meaning than shooting:

Other hyponyms of shooting include shoot, countershot, discharge, firing, firing off, gunfire, gunshot, shellfire, potshot.

shooting (noun)	headshot (noun)
the act of firing a projectile	a shot aimed at a person's head
killing someone by gunfire	an attempt to put the soccer ball into the net by using the head
	a photograph of a person's head