mountain vs spate

mountain and spate both are nouns.

Word	Noun	Adjective	Verb	Adverb
mountain	Yes	No	No	No
spate	Yes	No	No	No

As nouns, mountain and spate are synonyms defined as:

mountain and spate: (often followed by `of') a large number or amount or extent

mountain (noun)	spate (noun)
a land mass that projects well above its surroundings; higher than a hill	the occurrence of a water flow resulting from sudden rain or melting snow
(often followed by `of') a large number or amount or extent	a sudden forceful flow
	(often followed by `of') a large number or amount or extent