descend vs let down

descend and let down both are verbs.

Word	Noun	Adjective	Verb	Adverb
descend	No	No	Yes	No
let down	No	No	Yes	No

descend (verb)	let down (verb)
come as if by falling	fail to meet the hopes or expectations of
move downward and lower, but not necessarily all the way	move something or somebody to a lower position
do something that one considers to be below one's dignity
come from; be connected by a relationship of blood, for example