Lou·ver, Lou·vre n. Arch. A small lantern. See Lantern, 2 (a). [Written also lover, loover, lovery, and luffer.]
Louver boards or Louver boarding, the sloping boards set to shed rainwater outward in openings which are to be left otherwise unfilled; as belfry windows, the openings of a louver, etc.
Louver work, slatted work.