cul de sac vs passage

cul de sac and passage both are nouns.

Word	Noun	Adjective	Verb	Adverb
cul de sac	Yes	No	No	No
passage	Yes	No	No	No

As nouns, passage is a hypernym of cul de sac; that is, passage is a word with a broader meaning than cul de sac:

cul de sac (noun)	passage (noun)
a street with only one way in or out	a journey usually by ship
a passage with access only at one end	the passing of a law by a legislative body
	the act of passing something to another person
	the act of passing from one state or place to the next
	a bodily reaction of changing from one place or stage to another
	a way through or along which someone or something may pass
	a path or channel or duct through or along which something may pass
	a section of text; particularly a section of medium length
	a short section of a musical composition
	the motion of one object relative to another