touchscreen vs touch screen

touchscreen and touch screen both are nouns.

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

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

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

touchscreen (noun)	touch screen (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