U+10CA5 Old Hungarian Capital Letter Esz

The Wikipedia has the following information about this codepoint:

The Old Hungarian script or Hungarian runes (Hungarian: Székely-magyar rovás, 'székely-magyar runiform', or rovásírás) is an alphabetic writing system used for writing the Hungarian language. Modern Hungarian is written using the Latin-based Hungarian alphabet. The term "old" refers to the historical priority of the script compared with the Latin-based one. The Old Hungarian script is a child system of the Old Turkic alphabet.

The Hungarians settled the Carpathian Basin in 895. After the establishment of the Christian Hungarian kingdom, the old writing system was partly forced out of use during the rule of King Stephen, and the Latin alphabet was adopted. However, among some professions (e.g. shepherds who used a "rovás-stick" to officially track the number of animals) and in Transylvania, the script has remained in use by the Székely Magyars, giving its Hungarian name (székely) rovásírás. The writing could also be found in churches, such as that in the commune of Atid.

Its English name in the ISO 15924 standard is Old Hungarian (Hungarian Runic).