(ii) Challown (2474) - a window (as perforated):
An opening in the wall of a building. Windows varied in size, ornamentation, and style. They usually were protected by wooden latticework or grills. Some windows were large enough for a person to go through <Josh. 2:15; 1 Sam. 19:12>. Windows were often spoken of symbolically in the Bible, as at the time of the flood when "the windows of heaven were opened" <Gen. 7:11>. Also see HOUSE.
(from Nelson's Illustrated Bible Dictionary)
(Copyright (C) 1986, Thomas Nelson Publishers)
(iii) Window of opportunity / blessing - glimpse of God's will.
(iv) (a) 2:9