Source : Webster's Revised Unabridged Dictionary (1913)

Mussel \Mus"sel\, n. [See {Muscle}, 3.]
   1. (Zo["o]l.) Any one of many species of marine bivalve
      shells of the genus {Mytilus}, and related genera, of the
      family {Mytid[ae]}. The common mussel ({Mytilus edulis};
      see Illust. under {Byssus}), and the larger, or horse,
      mussel ({Modiola modiolus}), inhabiting the shores both of
      Europe and America, are edible. The former is extensively
      used as food in Europe.

   2. (Zo["o]l.) Any one of numerous species of {Unio}, and
      related fresh-water genera; -- called also {river mussel}.
      See {Naiad}, and {Unio}.

   {Mussel digger} (Zo["o]l.), the grayback whale. See {Gray
      whale}, under {Gray}.



   {Horse emmet} (Zo["o]l.), the horse ant.

   {Horse finch} (Zo["o]l.), the chaffinch. [Prov. Eng.]

   {Horse gentian} (Bot.), fever root.

   {Horse iron} (Naut.), a large calking iron.

   {Horse latitudes}, a space in the North Atlantic famous for
      calms and baffling winds, being between the westerly winds
      of higher latitudes and the trade winds. --Ham. Nav.
      Encyc.

   {Horse mackrel}. (Zo["o]l.)
      (a) The common tunny ({Orcynus thunnus}), found on the
          Atlantic coast of Europe and America, and in the
          Mediterranean.
      (b) The bluefish ({Pomatomus saltatrix}).
      (c) The scad.
      (d) The name is locally applied to various other fishes,
          as the California hake, the black candlefish, the
          jurel, the bluefish, etc.

   {Horse marine} (Naut.), an awkward, lubbery person; one of a
      mythical body of marine cavalry. [Slang]

   {Horse mussel} (Zo["o]l.), a large, marine mussel ({Modiola
      modiolus}), found on the northern shores of Europe and
      America.

   {Horse nettle} (Bot.), a coarse, prickly, American herb, the
      {Solanum Carolinense}.

   {Horse parsley}. (Bot.) See {Alexanders}.

   {Horse purslain} (Bot.), a coarse fleshy weed of tropical
      America ({Trianthema monogymnum}).

   {Horse race}, a race by horses; a match of horses in running
      or trotting.

   {Horse racing}, the practice of racing with horses.

   {Horse railroad}, a railroad on which the cars are drawn by
      horses; -- in England, and sometimes in the United States,
      called a {tramway}.

   {Horse run} (Civil Engin.), a device for drawing loaded
      wheelbarrows up an inclined plane by horse power.

   {Horse sense}, strong common sense. [Colloq. U.S.]

   {Horse soldier}, a cavalryman.

   {Horse sponge} (Zo["o]l.), a large, coarse, commercial sponge
      ({Spongia equina}).

   {Horse stinger} (Zo["o]l.), a large dragon fly. [Prov. Eng.]
      

   {Horse sugar} (Bot.), a shrub of the southern part of the
      United States ({Symplocos tinctoria}), whose leaves are
      sweet, and good for fodder.

   {Horse tick} (Zo["o]l.), a winged, dipterous insect
      ({Hippobosca equina}), which troubles horses by biting
      them, and sucking their blood; -- called also {horsefly},
      {horse louse}, and {forest fly}.

   {Horse vetch} (Bot.), a plant of the genus {Hippocrepis} ({H.
      comosa}), cultivated for the beauty of its flowers; --
      called also {horsehoe vetch}, from the peculiar shape of
      its pods.

   {Iron horse}, a locomotive. [Colloq.]

   {Salt horse}, the sailor's name for salt beef.

   {To look a gift horse in the mouth}, to examine the mouth of
      a horse which has been received as a gift, in order to
      ascertain his age; -- hence, to accept favors in a
      critical and thankless spirit. --Lowell.

   {To take horse}.
      (a) To set out on horseback. --Macaulay.
      (b) To be covered, as a mare.
      (c) See definition 7 (above).