(adj) not easily perturbed or excited or upset; marked by extreme calm and composure, Syn. unflappable, Example:hitherto imperturbable, he now showed signs of alarm; an imperturbable self-possession; unflappable in a crisis
The Collaborative International Dictionary of English (GCIDE) v.0.53 Collaborative International Dictionary (GCIDE)
n. 1. One who, or that which, flaps. [ 1913 Webster ]
2. See Flipper. “The flapper of a porpoise.” Buckley. [ 1913 Webster ]
3. A flat object used to make a flapping noise by striking another object. RHUD [ PJC ]
4. A flat and broad object hanging from a larger object, either flexible like rubber or hinged to allow a swinging motion; a flap.
5. A young woman who dresses in a modern, stylish manner and behaves unconventionally in social situations; -- a term used especially to refer to young women during the 1920's and their peculiar style of dress. [ PJC ]
Flapper skate (Zool.), a European skate (Raia intermedia). [ 1913 Webster ]