“Las Vegas” means the meadows. The Spanish were usually pragmatic when naming locations on their maps, e.g. Del Rio, El Paso (de Norte), and Presidio in Texas; Salida, La Junta, and Pueblo in Colorado; the Sierra Nevada in California; and El Camino Real’s everywhere.

'Ville' translates as "town" so "Green Town" :)

Similiarly in the UK 'Downs' is an old english word for hill so I'm always amused by a local 'Highdown Hill' ("HighHill Hill").