fun run vs funrun

fun run and funrun both are nouns.

Word	Noun	Adjective	Verb	Adverb
fun run	Yes	No	No	No
funrun	Yes	No	No	No

As nouns, fun run and funrun are synonyms defined as:

fun run and funrun: a footrace run for fun (often including runners who are sponsored for a charity)

fun run (noun)	funrun (noun)
a footrace run for fun (often including runners who are sponsored for a charity)	a footrace run for fun (often including runners who are sponsored for a charity)