hawk owl vs hooter

hawk owl and hooter both are nouns.

Word	Noun	Adjective	Verb	Adverb
hawk owl	Yes	No	No	No
hooter	Yes	No	No	No

As nouns, hooter is a hypernym of hawk owl; that is, hooter is a word with a broader meaning than hawk owl:

hawk owl: grey-and-white diurnal hawk-like owl of northern parts of the Northern Hemisphere
hooter: nocturnal bird of prey with hawk-like beak and claws and large head with front-facing eyes

Other hypernyms of hawk owl include bird of Minerva, bird of night, owl.

hawk owl (noun)	hooter (noun)
grey-and-white diurnal hawk-like owl of northern parts of the Northern Hemisphere	nocturnal bird of prey with hawk-like beak and claws and large head with front-facing eyes
	a device on an automobile for making a warning noise
	informal terms for the nose