Mark in the intersection of 58-Across and 43-Down

• FaГ§ade part
• Literally, "little z," in old Spanish
• Janet's fiancé in "The Rocky Horror Picture Show"
• Spanish diacritic
• French "c" feature, maybe
• Façade component
• Mark under a consonant in French, perhaps

Wikipedia Word definitions in Wikipedia
A cedilla ( ; from Spanish ), also known as cedilha (from Portuguese) or cédille (from French), is a hook or tail ( ¸ ) added under certain letters as a diacritical mark to modify their pronunciation. In Catalan , French , and Portuguese , it is used only ...

WordNet Word definitions in WordNet
n. a diacritical mark (,) placed below the letter c to indicate that it is pronounced as an s

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 ...