drain vs expend

drain is a noun but expend is not a noun.

Word	Noun	Adjective	Verb	Adverb
drain	Yes	No	Yes	No
expend	No	No	Yes	No

As verbs, expend is a hypernym of drain; that is, expend is a word with a broader meaning than drain:

Other hypernyms of drain include consume, deplete, eat, eat up, exhaust, run through, use, use up, wipe out.

drain (noun)	expend (noun)
emptying something accomplished by allowing liquid to run out of it
a gradual depletion of energy or resources
a pipe through which liquid is carried away
tube inserted into a body cavity (as during surgery) to remove unwanted material

drain (verb)	expend (verb)
empty of liquid; drain the liquid from	use up (resources or materials)
make weak	pay out
deplete of resources
flow off gradually