What does "Raven" [phonetic] means when used by ATC?
RAVNN (Pronounced Raven) is the name  of a waypoint in Maryland. From the FAA Fixes / Waypoints directory


  RAVNN MARYLAND BAL*C*174.00/22.98 OTT*C*070.89/12.17
  ENO*C*250.66/53.40 DCA*D*106.56 38-48-15.9900N 076-31-04.9100W


38°48'15.9900N 76°31'04.9100W(Google Maps link) is east of Washington.