touch screen vs touchscreen

touch screen and touchscreen both are nouns.

Word	Noun	Adjective	Verb	Adverb
touch screen	Yes	No	No	No
touchscreen	Yes	No	No	No

As nouns, touch screen and touchscreen are synonyms defined as:

touch screen and touchscreen: a computer display that enables the user to interact with the computer by touching areas on the screen

touch screen (noun)	touchscreen (noun)
a computer display that enables the user to interact with the computer by touching areas on the screen	a computer display that enables the user to interact with the computer by touching areas on the screen