Louver

Louver, Louvre or Luffer, in architecture, the lantern built upon the roof of the hall in ancient times to allow the smoke to escape when the fire was made on the pavement in the middle of the hall. The term is also applied to the flat overlapping slips of wood, glass, &c., with which such openings are closed, arranged to give ventilation without the admission of rain. Openings fitted with louvers are now utilized for the purposes of ventilation in schools and manufactories.

The word has been derived from the French l’ouvert, the “open” space. This, Minsheu’s guess, is now generally abandoned. The Old French form, of which the English is an adaptation, was lover or lovier. The medieval Latin lodium, lodarium, is suggested as the ultimate origin. Du Cange (Glossarium, s.v. “lodia”) defines it as lugurium, i.e. a small hut. The English form “louvre” is due to a confusion with the name of the palace in Paris. The origin of that name is also unknown; louverie, place of wolves, is one of the suggestions, the palace being supposed to have originally been a hunting-box (see Paris).