footrace vs funrun

footrace and funrun both are nouns.

Word	Noun	Adjective	Verb	Adverb
footrace	Yes	No	No	No
funrun	Yes	No	No	No

As nouns, funrun is a hyponym of footrace; that is, funrun is a word with a more specific, narrower meaning than footrace:

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

Other hyponyms of footrace include fun run, marathon, obstacle race, steeplechase, track event.

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