precomposed character

A precomposed character (alternatively decomposable character) is a Unicode entity that can be decomposed into an equivalent string of several other characters. Typically, a precomposed character is decomposed into the main character and a combining diacritical mark.The precomposed characters are included in the character set to aid computer systems with incomplete Unicode support, where decomposed equivalent characters may render incorrectly.Similarly, ligatures are precompositions of their constituent letters or graphemes.
See more at Wikipedia.org...