breach vs falling out

breach and falling out both are nouns.

Word	Noun	Adjective	Verb	Adverb
breach	Yes	No	Yes	No
falling out	Yes	No	No	No

As nouns, breach and falling out are synonyms defined as:

breach and falling out: a personal or social separation (as between opposing factions)

Other synonyms of breach include break, rift, rupture, severance.

breach (noun)	falling out (noun)
a failure to perform some promised act or obligation	a personal or social separation (as between opposing factions)
a personal or social separation (as between opposing factions)
an opening (especially a gap in a dike or fortification)

breach (verb)	falling out (verb)
make an opening or gap in
act in disregard of laws, rules, contracts, or promises