noun A diacritical mark ⟨¸⟩ placed beneath a letter to modify its pronunciation, used in the orthographies of many languages, such as under c in Catalan, French and Portuguese to indicate /s/ rather than /k/ (e.g. Catalan força, French façade, Portuguese açaí) and in other languages to modify the pronunciation of the letter c (e.g. from /d͡ʒ/ to /t͡ʃ/ in Turkish) or of other letters.