bicorn

1. (historical) A two-cornered hat, worn by European and American military and naval officers from the 1790s.Examples: "Just last Sunday, one of the estimated 20 surviving bicorne hats worn by Napoleon was sold at auction for €1.9mn, a price that vindicates the famous epigram, attributed to the emperor among others, that there is but one step separating the sublime from the ridiculous."historical

2. (mathematics) A plane curve having two cusps.

3. (rare) A beast having two horns, either real or fictional.Examples: "What a stir about nothing! Phenicopter is no more (pace Dr Septimus Wind and his eyriecal friend, Dr Eagles) than the common flamingo (simplex). Why ask such silly questions? What, for example, is a caterpillar? and why so denominated? There is the common quail as there is the common flag-beetle. A king (or queen) fisher might devour eaglets, but what is that to the spider in ordinary? and what has the spider to do with the Neapolitan tarentella? Unicorns and bicorns may be gregarious without even subterfuge or sideral ornament."; "But as far as horned species are concerned, if these natural defences were the result of buntings, we should have races of unicorns, not bicorns, that is, the horns ought to have shot out on the spots of the natural “stimulus” from the foreheads, not from the sides!"; "Buttings and batterings mean that the points of impact would be the frontal portion of the skull, so that if such batterings and buttings had anything to do with the inducing the flow of blood thereto and the consequent inducement of growth, the result would have been unicorns, not bicorns in which the horns appeared at points not affected by the impacts."rare