pluviometer vs rain gage

pluviometer and rain gage both are nouns.

Word	Noun	Adjective	Verb	Adverb
pluviometer	Yes	No	No	No
rain gage	Yes	No	No	No

As nouns, pluviometer and rain gage are synonyms defined as:

pluviometer and rain gage: gauge consisting of an instrument to measure the quantity of precipitation

Other synonyms of pluviometer include rain gauge, udometer.

pluviometer (noun)	rain gage (noun)
gauge consisting of an instrument to measure the quantity of precipitation	gauge consisting of an instrument to measure the quantity of precipitation