hydrant vs discharge pipe

hydrant and discharge pipe both are nouns.

Word	Noun	Adjective	Verb	Adverb
hydrant	Yes	No	No	No
discharge pipe	Yes	No	No	No

As nouns, discharge pipe is a hypernym of hydrant; that is, discharge pipe is a word with a broader meaning than hydrant:

hydrant: a discharge pipe with a valve and spout at which water may be drawn from the mains of waterworks
discharge pipe: a pipe through which fluids can be discharged

hydrant (noun)	discharge pipe (noun)
a discharge pipe with a valve and spout at which water may be drawn from the mains of waterworks	a pipe through which fluids can be discharged
a faucet for drawing water from a pipe or cask