a northern duck (dafila acuta), native of both continents. the adult male has a long, tapering tail. called also gray duck, piketail, piket-tail, spike-tail, split-tail, springtail, sea pheasant, and gray widgeon.-the sharp-tailed grouse of the great plains and rocky mountains (pediocaetes phasianellus); -- called also pintailed grouse, pintailed chicken, springtail, and sharptail.