abat-jour

Meaning

1. A skylight, or any beveled aperture made in the wall of an apartment or in a roof, for the better admission of light from above.
2. A sloping, box-like structure, flaring upward and open at the top, attached to a window on the outside, to prevent those within from seeing objects below, or for the purpose of directing light downward into the window.

Synonyms

lampshade

Etymology

From French abattre jour (any contrivance or apparatus to admit light, or to throw it in a desired direction, as a lamp-shade).