electronic bulletin board vs bulletin board system

electronic bulletin board and bulletin board system both are nouns.

Word	Noun	Adjective	Verb	Adverb
electronic bulletin board	Yes	No	No	No
bulletin board system	Yes	No	No	No

As nouns, electronic bulletin board and bulletin board system are synonyms defined as:

electronic bulletin board and bulletin board system: a computer that is running software that allows users to leave messages and access information of general interest

Other synonyms of electronic bulletin board include bbs, bulletin board.

electronic bulletin board (noun)	bulletin board system (noun)
a computer that is running software that allows users to leave messages and access information of general interest	a computer that is running software that allows users to leave messages and access information of general interest