Unknown; possibly a variant of Cassian or Cason
The exact etymology of Casin is unclear. It is likely a modern American phonetic variant of the English surname-name Cason or the Latin-derived Cassian, which means 'hollow' or 'belonging to Cassius'. Due to its rarity, it functions as a unique, contemporary creation.
Fewer than 5 boys were named Casin in 2025.
US births per 5-year period, 1990–present (SSA data).
