Source : Webster's Revised Unabridged Dictionary (1913)

Fenestral \Fe*nes"tral\, a. [L. fenestra a window.]
   1. (Arch.) Pertaining to a window or to windows.

   2. (Anat.) Of or pertaining to a fenestra.

Fenestral \Fe*nes"tral\, n. (Arch.)
   A casement or window sash, closed with cloth or paper instead
   of glass. --Weale.

Source : WordNet®

fenestral
     adj 1: of or relating to or having a fenestra
     2: of or relating to windows