drain vs soil pipe

drain and soil pipe both are nouns.

Word	Noun	Adjective	Verb	Adverb
drain	Yes	No	Yes	No
soil pipe	Yes	No	No	No

As nouns, soil pipe is a hyponym of drain; that is, soil pipe is a word with a more specific, narrower meaning than drain:

Other hyponyms of drain include culvert, scupper, cloaca, sewer, sewerage, trap.

drain (noun)	soil pipe (noun)
emptying something accomplished by allowing liquid to run out of it	drain that conveys liquid waste from toilets, etc.
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)	soil pipe (verb)
empty of liquid; drain the liquid from
make weak
deplete of resources
flow off gradually