1. 
[syn: southeast, southeastern, southeasterly]
2.  of a region of the United States generally including Alabama;  Georgia;  Florida;  Tennessee;  South Carolina;  North Carolina; 
The Collaborative International Dictionary of English v.0.48:
Southeastern \South`east"ern\, a.
   Of or pertaining to the southeast; southeasterly.
   [1913 Webster] Southeastward
WordNet (r) 3.0 (2006):
southeastern
    adj 1: situated in or oriented toward the southeast [syn:
           southeast, southeastern, southeasterly]
    2: of a region of the United States generally including Alabama;
       Georgia; Florida; Tennessee; South Carolina; North Carolina