frost heaving vs frost heave

frost heaving and frost heave both are nouns.

Word	Noun	Adjective	Verb	Adverb
frost heaving	Yes	No	No	No
frost heave	Yes	No	No	No

As nouns, frost heaving and frost heave are synonyms defined as:

frost heaving and frost heave: upthrust of ground or pavement caused by the freezing of moist soil

frost heaving (noun)	frost heave (noun)
upthrust of ground or pavement caused by the freezing of moist soil	upthrust of ground or pavement caused by the freezing of moist soil