Addition to a letter

• Letter attachment?
• Mark placed under the letter c
• Under-C hook
• Mark indicating a softened consonant
• A diacritical mark (,) placed below the letter c to indicate that it is pronounced as an s
• Mark suggesting a 'c' should be pronounced an 's'
• Cousin of the tilde and umlaut
• Façade part
• Literally, "little z," in old Spanish

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
c.1600, from Spanish cedilla , zedilla , literally "little z," from a Latin-like diminutive of Greek zeta "the letter 'z'." The mark (formerly also used in Spanish) was derived from that letter and indicates a "soft" sound in letters in positions where ...