instillator vs apparatus

instillator and apparatus both are nouns.

Word	Noun	Adjective	Verb	Adverb
instillator	Yes	No	No	No
apparatus	Yes	No	No	No

As nouns, apparatus is a hypernym of instillator; that is, apparatus is a word with a broader meaning than instillator:

instillator: medical apparatus that puts a liquid into a cavity drop by drop
apparatus: equipment designed to serve a specific function

Other hypernyms of instillator include setup.

instillator (noun)	apparatus (noun)
medical apparatus that puts a liquid into a cavity drop by drop	equipment designed to serve a specific function
	(anatomy) a group of body parts that work together to perform a given function