gage vs rain gage

gage and rain gage both are nouns.

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

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

gage: a measuring instrument for measuring and indicating a quantity such as the thickness of wire or the amount of rain etc.
rain gage: gauge consisting of an instrument to measure the quantity of precipitation

gage (noun)	rain gage (noun)
a measuring instrument for measuring and indicating a quantity such as the thickness of wire or the amount of rain etc.	gauge consisting of an instrument to measure the quantity of precipitation
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gage (verb)	rain gage (verb)
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