/fen'euh stray"sheuhn/ , n.
1. the design and disposition of windows and other exterior openings of a building.
2. Furniture. an ornamental motif having the form of a blind arcade or arch, as in medieval cabinetwork.
3. Med. , Surg.
a. a perforation in a structure.
b. an operation to effect such an opening.
c. Also called fenestration operation, Lempert operation . the creation of an artificial opening into the labyrinth of the ear to restore hearing loss from otosclerosis.
[ 1840-50; fenestrat ( us ) (see FENESTRATED) + -ION ]