doughnut fryer vs doughnut machine

doughnut fryer and doughnut machine both are nouns.

Word	Noun	Adjective	Verb	Adverb
doughnut fryer	Yes	No	No	No
doughnut machine	Yes	No	No	No

As nouns, doughnut fryer and doughnut machine are synonyms defined as:

doughnut fryer and doughnut machine: a machine used to fry large quantities of doughnuts at once.

Other synonyms of doughnut fryer include donut fryer, donut machine.

doughnut fryer (noun)	doughnut machine (noun)
a machine used to fry large quantities of doughnuts at once.	a machine used to fry large quantities of doughnuts at once.