common salt vs table salt

common salt and table salt both are nouns.

Word	Noun	Adjective	Verb	Adverb
common salt	Yes	No	No	No
table salt	Yes	No	No	No

As nouns, common salt and table salt are synonyms defined as:

common salt and table salt: white crystalline form of especially sodium chloride used to season and preserve food

Other synonyms of common salt include salt.

common salt (noun)	table salt (noun)
white crystalline form of especially sodium chloride used to season and preserve food	white crystalline form of especially sodium chloride used to season and preserve food
a white crystalline solid consisting mainly of sodium chloride (NaCl)