I. ˈ ̷ ̷ˌ ̷ ̷ noun
Etymology: after Bluebeard, a fairy-tale character who murdered six wives, translation of French Barbe-Bleue, the best-known literary version being by Charles Perrault died 1703 French writer
: a man who marries and kills one wife after another
II. adjective
Etymology: after Bluebeard, the fairy-tale character; from his having hidden the bodies of his murdered wives in a room which his seventh wife was forbidden to enter
: not to be entered or explored : forbidden
the bluebeard room of the house — Thomas De Quincey
III. noun
( -s )
Etymology: blue (I) + beard; from the appearance of the flower
: a shrub of the genus Caryopteris ; especially : an autumn-blooming Asiatic ornamental ( C. incana ) with blue flowers suggesting those of a spirea — called also blue spirea