sitting room vs living room

sitting room and living room both are nouns.

Word	Noun	Adjective	Verb	Adverb
sitting room	Yes	No	No	No
living room	Yes	No	No	No

As nouns, sitting room and living room are synonyms defined as:

sitting room and living room: a room in a private house or establishment where people can sit and talk and relax

Other synonyms of sitting room include front room, living-room, parlor, parlour.

sitting room (noun)	living room (noun)
a room in a private house or establishment where people can sit and talk and relax	a room in a private house or establishment where people can sit and talk and relax