any of several birds of prey of the family Falconidae, especially of the genus Falco, usually distinguished by long, pointed wings, a hooked beak with a toothlike notch on each side of the upper bill, and swift, agile flight, typically diving to seize prey: some falcon species are close to extinction.
mid-13c., from O.Fr. faucon, from L.L. falconem (nom. falco), probably from L. falx (gen. falcis) "sickle," usually said to be so called for the shape of its talons or beak, but possibly from the shape of its spread wings. The other theory is that falx is of Germanic origin, which is supported by the antiquity of the word in Germanic but opposed by those who point out that falconry by all evidences was imported from the East, and the Germans got it from the Romans, not the other way around.