Diacritic /(?)/
Di·a·crit·ic
Diacritic
a.
-
That separates or distinguishes; -- applied to points or marks used to distinguish letters of similar form, or different sounds of the same letter, as, ā, ă, ä, ō, ŏ, etc.
A glance at this typography will reveal great difficulties, which diacritical marks necessarily throw in the way of both printer and writer.