soda vs soda water

soda and soda water both are nouns.

Word	Noun	Adjective	Verb	Adverb
soda	Yes	No	No	No
soda water	Yes	No	No	No

As nouns, soda and soda water are synonyms defined as:

soda and soda water: a sweet drink containing carbonated water and flavoring

Other synonyms of soda include pop, soda pop, tonic.

soda (noun)	soda water (noun)
a sweet drink containing carbonated water and flavoring	effervescent beverage artificially charged with carbon dioxide
a sodium salt of carbonic acid; used in making soap powders and glass and paper	a sweet drink containing carbonated water and flavoring