What does "lancet" mean?

Lancet: (Metal.) An iron bar used for tapping a melting furnace. Knight. Lancet arch (Arch.), a pointed arch, of which the width, or span, is narrow compared with the height. -- Lancet architecture, a name given to a style of architecture, in which lancet arches are common; -- peculiar to England and 13th century. -- Lancet fish. (Zoöl.) (a) A large, voracious, deep-sea fish (Alepidosaurus ferox), having long, sharp, lancetlike teeth. (b) The doctor, or surgeon fish.