nongraphic character
Computing term for characters that do not produce a visible mark, such as control characters, spaces, or formatting codes.
Nongraphic characters include line breaks and tabs.
制御文字 (control character) is a subset of non-graphic characters that specifically control devices or formatting, while 非図形文字 is a broader category including any character without a visible glyph.
Compound of 非 (non-) + 図形 (graphic) + 文字 (character), a direct translation of the English computing term 'nongraphic character'.