carbonated water vs seltzer

carbonated water and seltzer both are nouns.

Word	Noun	Adjective	Verb	Adverb
carbonated water	Yes	No	No	No
seltzer	Yes	No	No	No

As nouns, carbonated water and seltzer are synonyms defined as:

carbonated water and seltzer: effervescent beverage artificially charged with carbon dioxide

Other synonyms of carbonated water include club soda, soda water, sparkling water.

carbonated water (noun)	seltzer (noun)
effervescent beverage artificially charged with carbon dioxide	naturally effervescent mineral water
	effervescent beverage artificially charged with carbon dioxide