water down vs debase

water down and debase both are verbs.

Word	Noun	Adjective	Verb	Adverb
water down	No	No	Yes	No
debase	No	No	Yes	No

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

water down: thin by adding water to
debase: corrupt, debase, or make impure by adding a foreign or inferior substance; often by replacing valuable ingredients with inferior ones

Other hypernyms of water down include adulterate, dilute, load, stretch.

water down (verb)	debase (verb)
make less strong or intense	lower in value by increasing the base-metal content
thin by adding water to	corrupt, debase, or make impure by adding a foreign or inferior substance; often by replacing valuable ingredients with inferior ones
	corrupt morally or by intemperance or sensuality