respirator vs respire

respirator is a noun but respire is not a noun.

Word	Noun	Adjective	Verb	Adverb
respirator	Yes	No	No	No
respire	No	No	Yes	No

respirator (noun)	respire (noun)
a breathing device for administering long-term artificial respiration
a protective mask with a filter; protects the face and lungs against poisonous gases

respirator (verb)	respire (verb)
	draw air into, and expel out of, the lungs
	undergo the biomedical and metabolic processes of respiration by taking up oxygen and producing carbon monoxide
	breathe easily again, as after exertion or anxiety