Source : Webster's Revised Unabridged Dictionary (1913)

Easterly \East"er*ly\, a.
   1. Coming from the east; as, it was easterly wind.

   2. Situated, directed, or moving toward the east; as, the
      easterly side of a lake; an easterly course or voyage.

Easterly \East"er*ly\, adv.
   Toward, or in the direction of, the east.

Source : WordNet®

easterly
     adj 1: lying in or toward the east; "the east side of NY"; "eastern
            cities" [syn: {eastern}]
     2: from the east; used especially of winds; "an east wind";
        "the winds are easterly" [syn: {eastern}]
     n : a wind from the east [syn: {east wind}, {easter}]
     adv : from the east; "the winds blew easterly all night" [ant: {westerly}]