e.g. https://en.wikipedia.org/wiki/Hangul https://en.wikipedia.org/wiki/Cyrillic and I guess even https://en.wikipedia.org/wiki/Klingon_language
This is different than the meaning of https://en.wikipedia.org/wiki/Natural_language and https://en.wikipedia.org/wiki/Constructed_language
I guess if you want to get pedantic a better term might be "Orthographic design".