sight-read vs sightread

sight-read and sightread both are verbs.

Word	Noun	Adjective	Verb	Adverb
sight-read	No	No	Yes	No
sightread	No	No	Yes	No

As verbs, sight-read and sightread are synonyms defined as:

sight-read and sightread: perform music from a score without having seen the score before

sight-read (verb)	sightread (verb)
perform music from a score without having seen the score before	perform music from a score without having seen the score before