rain shower vs sprinkle

rain shower and sprinkle both are nouns.

Word	Noun	Adjective	Verb	Adverb
rain shower	Yes	No	No	No
sprinkle	Yes	No	Yes	No

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

Other hyponyms of rain shower include scattering, sprinkling.

rain shower (noun)	sprinkle (noun)
a brief period of precipitation	the act of sprinkling or splashing water
	a light shower that falls in some locations and not others nearby

rain shower (verb)	sprinkle (verb)
	scatter with liquid; wet lightly
	cause (a liquid) to spatter about, especially with force
	distribute loosely
	rain gently