drain vs emptying

drain and emptying both are nouns.

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

As nouns, emptying is a hypernym of drain; that is, emptying is a word with a broader meaning than drain:

Other hypernyms of drain include evacuation, voidance.

drain (noun)	emptying (noun)
emptying something accomplished by allowing liquid to run out of it	the act of removing the contents of something
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)	emptying (verb)
empty of liquid; drain the liquid from
make weak
deplete of resources
flow off gradually