outpouring vs natural spring

outpouring and natural spring both are nouns.

Word	Noun	Adjective	Verb	Adverb
outpouring	Yes	No	No	No
natural spring	Yes	No	No	No

As nouns, outpouring and natural spring are synonyms defined as:

Other synonyms of outpouring include fountain, outflow, spring.

outpouring (noun)	natural spring (noun)
a large flow	a natural flow of ground water
the rapid and continuous delivery of linguistic communication (spoken or written)
the pouring forth of a fluid
a sudden rapid flow (as of water)
a natural flow of ground water