followup vs follow-up

followup and follow-up both are nouns.

Word	Noun	Adjective	Verb	Adverb
followup	Yes	No	No	No
follow-up	Yes	No	No	No

As nouns, followup and follow-up are synonyms defined as:

followup and follow-up: a subsequent examination of a patient for the purpose of monitoring earlier treatment

Other synonyms of followup include reexamination, review.

As nouns, followup and follow-up are synonyms defined as:

followup and follow-up: an activity that continues something that has already begun or that repeats something that has already been done

As nouns, followup and follow-up are synonyms defined as:

followup and follow-up: a piece of work that exploits or builds on earlier work

followup (noun)	follow-up (noun)
a subsequent examination of a patient for the purpose of monitoring earlier treatment	a subsequent examination of a patient for the purpose of monitoring earlier treatment
an activity that continues something that has already begun or that repeats something that has already been done	an activity that continues something that has already begun or that repeats something that has already been done
a piece of work that exploits or builds on earlier work	a piece of work that exploits or builds on earlier work