Source : Webster's Revised Unabridged Dictionary (1913)

Northwest \North`west"\, n. [AS. nor[eth]west.]
   The point in the horizon between the north and west, and
   equally distant from each; the northwest part or region.

Northwest \North`west"\, a.
   1. Pertaining to, or in the direction of, the point between
      the north and west; being in the northwest; toward the
      northwest, or coming from the northwest; as, the northwest
      coast.

   2. Coming from the northwest; as, a northwest wind.

   {Northwest passage}, a passage or communication by sea
      between the Atlantic and Pacific oceans along the north
      coast of America, long sought for by navigators.

Northwest \North`west"\, adv.
   Toward the northwest.

Source : WordNet®

Northwest
     n 1: the northwestern region of the United States [syn: {northwestern
          United States}]
     2: the compass point midway between north and west; at 315
        degrees [syn: {nor'-west}, {NW}]