big board vs New York Stock Exchange

big board and New York Stock Exchange both are nouns.

Word	Noun	Adjective	Verb	Adverb
big board	Yes	No	No	No
New York Stock Exchange	Yes	No	No	No

As nouns, big board and New York Stock Exchange are synonyms defined as:

big board and New York Stock Exchange: a stock exchange in New York, located at 11 Wall Street

Other synonyms of big board include N. Y. Stock Exchange, NYSE.

big board (noun)	New York Stock Exchange (noun)
the large display board at the New York Stock Exchange that reports on stocks traded on the exchange	a stock exchange in New York, located at 11 Wall Street
a stock exchange in New York, located at 11 Wall Street