guest worker vs guestworker

guest worker and guestworker both are nouns.

Word	Noun	Adjective	Verb	Adverb
guest worker	Yes	No	No	No
guestworker	Yes	No	No	No

As nouns, guest worker and guestworker are synonyms defined as:

guest worker and guestworker: a person with temporary permission to work in another country

guest worker (noun)	guestworker (noun)
a person with temporary permission to work in another country	a person with temporary permission to work in another country