identifier vs symbol

identifier and symbol both are nouns.

Word	Noun	Adjective	Verb	Adverb
identifier	Yes	No	No	No
symbol	Yes	No	No	No

As nouns, symbol is a hypernym of identifier; that is, symbol is a word with a broader meaning than identifier:

identifier: a symbol that establishes the identity of the one bearing it
symbol: an arbitrary sign (written or printed) that has acquired a conventional significance

identifier (noun)	symbol (noun)
a symbol that establishes the identity of the one bearing it	something visible that by association or convention represents something else that is invisible
	an arbitrary sign (written or printed) that has acquired a conventional significance