The Collaborative International Dictionary of English v.0.48:

Southward \South"ward\ (?; colloq. ?), Southwards \South"wards\
   (?; colloq. ?), adv.
   Toward the south, or toward a point nearer the south than the
   east or west point; as, to go southward.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Southward \South"ward\, a.
   Toward the south.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Southward \South"ward\, n.
   The southern regions or countries; the south. --Sir W.
   Raleigh.
   [1913 Webster]

WordNet (r) 3.0 (2006):

southward
    adv 1: toward the south; "the ship turned southerly" [syn:
           southerly, southward, southwards]
    adj 1: moving toward the south; "a southbound train" [syn:
           southbound, southward]
    n 1: the cardinal compass point that is at 180 degrees [syn:
         south, due south, southward, S]

Moby Thesaurus II by Grady Ward, 1.0:

28 Moby Thesaurus words for "southward":
   S, cardinal points, compass card, compass rose, degrees, east,
   eastward, half points, lubber line, north, northeast, northward,
   northwest, occident, orient, quarter points, rhumb, south,
   south about, southeast, southerly, southwardly, southwards,
   southwest, sunrise, sunset, west, westward