rampart vs battlement

rampart and battlement both are nouns.

Word	Noun	Adjective	Verb	Adverb
rampart	Yes	No	No	No
battlement	Yes	No	No	No

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

rampart: an embankment built around a space for defensive purposes
battlement: a rampart built around the top of a castle with regular gaps for firing arrows or guns

Other hyponyms of rampart include bailey, crenelation, crenellation, earthwork, fraise, merlon.

rampart (noun)	battlement (noun)
an embankment built around a space for defensive purposes	a rampart built around the top of a castle with regular gaps for firing arrows or guns