chat room vs chatroom

chat room and chatroom both are nouns.

Word	Noun	Adjective	Verb	Adverb
chat room	Yes	No	No	No
chatroom	Yes	No	No	No

As nouns, chat room and chatroom are synonyms defined as:

chat room and chatroom: a site on the internet where a number of users can communicate in real time (typically one dedicated to a particular topic)

chat room (noun)	chatroom (noun)
a site on the internet where a number of users can communicate in real time (typically one dedicated to a particular topic)	a site on the internet where a number of users can communicate in real time (typically one dedicated to a particular topic)