hall vs narthex

hall and narthex both are nouns.

Word	Noun	Adjective	Verb	Adverb
hall	Yes	No	No	No
narthex	Yes	No	No	No

As nouns, narthex is a hyponym of hall; that is, narthex is a word with a more specific, narrower meaning than hall:

hall (noun)	narthex (noun)
a large building for meetings or entertainment	a vestibule leading to the nave of a church
a large room for gatherings, receiving guests, or entertainment	portico at the west end of an early Christian basilica or church
an interior passage or corridor onto which rooms open
a college or university building containing living quarters for students
a large entrance or reception room or area
the large room of a manor or castle
a large and imposing house
a large building used by a college or university for teaching or research