2. Medicine Diagnostic or distinctive.
A mark, such as the cedilla of façade or the acute accents of résumé, added to a letter to indicate a special phonetic value or distinguish words that are otherwise graphically identical.
[Greek diakritikos, distinguishing, from diakritos, distinguished, from diakrīnein, to distinguish : dia-, apart; see DIA- + krīnein, to separate; see krei- in the Appendix of Indo-European roots.]
(click for a larger image)diacritic
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