dark-field microscope vs ultramicroscope

dark-field microscope and ultramicroscope both are nouns.

Word	Noun	Adjective	Verb	Adverb
dark-field microscope	Yes	No	No	No
ultramicroscope	Yes	No	No	No

As nouns, dark-field microscope and ultramicroscope are synonyms defined as:

dark-field microscope and ultramicroscope: light microscope that uses scattered light to show particles too small to see with ordinary microscopes

dark-field microscope (noun)	ultramicroscope (noun)
light microscope that uses scattered light to show particles too small to see with ordinary microscopes	light microscope that uses scattered light to show particles too small to see with ordinary microscopes