n-char:
any member of the translation character set except the U+007d right curly bracket or new-line character

The universal-character-name construct provides a way to name any element in the translation character set using just the basic character set.

A universal-character-name of the form \u hex-quad, \U hex-quad hex-quad, or \u{simple-hexadecimal-digit-sequence} designates the character in the translation character set whose Unicode scalar value is the hexadecimal number represented by the sequence of hexadecimal-digits in the universal-character-name.

The program is ill-formed if that number is not a Unicode scalar value.

A universal-character-name that is a named-universal-character designates the corresponding character in the Unicode Standard (chapter 4.8 Name) if the n-char-sequence is equal to its character name or to one of its character name aliases of type “control”, “correction”, or “alternate”; otherwise, the program is ill-formed.