Alexa

Alexa can be considered a shorter version of Alexandra, which is itself a feminine version of Alexander, or it can be considered an alternate version of Alexis, which itself comes from the Greek name Alexius. In any case, Alexander and Alexius both mean "to defend." Alexa is currently enjoying a popularity spike, and is a top 100 name in the U.S. for baby girls. Nevertheless, if you are considering this name for your baby girl, I'd recommend going with the full version, Alexandra, simply because it is so much more versatile, and you can still call her Alexa.