\Lan"cet\, n. [F. lancette, dim. of lance lance. See
{Lance}.]
1. A surgical instrument of various forms, commonly
   sharp-pointed and two-edged, used in venesection, and in
   opening abscesses, etc.
2. (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}. (Zo["o]l.)
   (a) A large, voracious, deep-sea fish ({Alepidosaurus
       ferox}), having long, sharp, lancetlike teeth.
   (b) The doctor, or surgeon fish.