ergometer vs dynamometer

ergometer and dynamometer both are nouns.

Word	Noun	Adjective	Verb	Adverb
ergometer	Yes	No	No	No
dynamometer	Yes	No	No	No

As nouns, ergometer and dynamometer are synonyms defined as:

ergometer and dynamometer: measuring instrument designed to measure power

ergometer (noun)	dynamometer (noun)
measuring instrument designed to measure power	measuring instrument designed to measure power