runup vs run-up

runup and run-up both are nouns.

Word	Noun	Adjective	Verb	Adverb
runup	Yes	No	No	No
run-up	Yes	No	No	No

As nouns, runup and run-up are synonyms defined as:

runup and run-up: a substantial increase over a relatively short period of time

runup (noun)	run-up (noun)
a substantial increase over a relatively short period of time	the approach run during which an athlete gathers speed
	a substantial increase over a relatively short period of time