n. (also louver)
1. each of a set of overlapping slats designed to admit air and some light and exclude rain.
2 a domed structure on a roof with side openings for ventilation etc.
Phrases and idioms:
louvre-boards the slats or boards making up a louvre.
Derivatives:
louvred adj.
Etymology: ME f. OF lover, lovier skylight, prob. f. Gmc