rope down vs abseil

rope down is not a noun while abseil is a noun.

Word	Noun	Adjective	Verb	Adverb
rope down	No	No	Yes	No
abseil	Yes	No	Yes	No

As verbs, rope down and abseil are synonyms defined as:

Other synonyms of rope down include rappel.

rope down (noun)	abseil (noun)
	(mountaineering) a descent of a vertical cliff or wall made by using a doubled rope that is fixed to a higher point and wrapped around the body

rope down (verb)	abseil (verb)
descend by means of a rappel	descend by means of a rappel