| imperturbable | (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 |
| Imperturbability | n. The state or quality of being imperturbable. [ 1913 Webster ] |
| Imperturbable | a. [ L. imperturbabilis; pref. im- not + perturbare to disturb: cf. F. imperturbable. See Perture. ] Incapable of being disturbed or disconcerted; |
| Imperturbably | adv. In an imperturbable manner; calmly. C. Bronté. [ 1913 Webster ] |