sterilizer vs digester

sterilizer and digester both are nouns.

Word	Noun	Adjective	Verb	Adverb
sterilizer	Yes	No	No	No
digester	Yes	No	No	No

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

sterilizer: a device for heating substances above their boiling point; used to manufacture chemicals or to sterilize surgical instruments
digester: autoclave consisting of a vessel in which plant or animal materials are digested

Other hyponyms of sterilizer include pressure cooker.

sterilizer (noun)	digester (noun)
a device for heating substances above their boiling point; used to manufacture chemicals or to sterilize surgical instruments	autoclave consisting of a vessel in which plant or animal materials are digested