Fitz

Much like Mac, Fitz is a name meaning "son of." With French and Norman origins, it comes from the word fils or filz, meaning "son," which came from the Latin word filius. You'll often see this name used as a prefix for surnames like Fitzgerald or Fitzpatrick, but it's just as capable of standing on its own. These surnames can also be used as first names, like Pride and Prejudice's Fitzwilliam Darcy, making Fitz a snappy nickname. If you decide to use one of your own names for baby's middle name, Fitz will prove to be extra fitting.