leaven vs prove

leaven is a noun but prove is not a noun.

Word	Noun	Adjective	Verb	Adverb
leaven	Yes	No	Yes	No
prove	No	No	Yes	No

As verbs, leaven and prove are synonyms defined as:

Other synonyms of leaven include raise.

leaven (noun)	prove (noun)
an influence that works subtly to lighten or modify something
a substance used to produce fermentation in dough or a liquid

leaven (verb)	prove (verb)
cause to puff up with a leaven	establish the validity of something, as by an example, explanation or experiment
	obtain probate of
	prove formally; demonstrate by a mathematical, formal proof
	provide evidence for
	take a trial impression of
	cause to puff up with a leaven
	increase in volume
	put to the test, as for its quality, or give experimental use to
	be shown or be found to be