The name Cia is a girl's name meaning "of the moon". Cia and is often added to lists like Short Baby Names and discussed in our forums with posts like "Names on NB that make you go WOW!".
From the experts:
What's Cia short for? Cynthia or most any other C-name. Stylish in its sleek Mia-Nia minimalist feel, but may remind some of the Central Intelligence Agency.