a diacritical mark (,) placed below the letter c to indicate that it is pronounced as an s
In the spelling of Catalan, French, Portuguese and some other languages, a mark ⟨¸⟩ sometimes placed under the letter c to indicate that it is pronounced /s/ rather than /k/, as in Catalan força, French menaçant, and Portuguese almoço, and also used in various other languages to change the sounds of other letters.