let down vs bilk

let down and bilk both are verbs.

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

As verbs, bilk is a hypernym of let down; that is, bilk is a word with a broader meaning than let down:

Other hypernyms of let down include baffle, cross, foil, frustrate, queer, scotch, spoil, thwart.

let down (verb)	bilk (verb)
fail to meet the hopes or expectations of	escape, either physically or mentally
move something or somebody to a lower position	evade payment to
	cheat somebody out of what is due, especially money
	hinder or prevent (the efforts, plans, or desires) of