dilute vs weaken

dilute is an adjective but weaken is not an adjective.

Word	Noun	Adjective	Verb	Adverb
dilute	No	Yes	Yes	No
weaken	No	No	Yes	No

As verbs, weaken is a hypernym of dilute; that is, weaken is a word with a broader meaning than dilute:

dilute (adjective)	weaken (adjective)
reduced in strength or concentration or quality or purity

dilute (verb)	weaken (verb)
lessen the strength or flavor of a solution or mixture	become weaker
corrupt, debase, or make impure by adding a foreign or inferior substance; often by replacing valuable ingredients with inferior ones	lessen the strength of
	reduce the level or intensity or size or scope of
	lessen in force or effect
	destroy property or hinder normal operations