Astra is a girl who is too cool. When people see an Astra on the street, they say, "Man, that girl is so damn hip. I wish I was/was with that girl." You can tell an Astra from a mile away because they usually have rad tattoos and are listening to super cool underground music on their Ipod. If you run into a girl at some local show and she's the only on who knows the words to all the songs, you know it's an Astra.
"My God, check that girl's hip swagger. She's totally an Astra."