Snail trefoil

Snail \Snail\ (sn[=a]l), n. [OE. snaile, AS. sn[ae]gel, snegel,
   sn[ae]gl; akin to G. schnecke, OHG. snecko, Dan. snegl, Icel.
   snigill.]
   1. (Zool.)
      (a) Any one of numerous species of terrestrial
          air-breathing gastropods belonging to the genus Helix
          and many allied genera of the family {Helicidae}. They
          are abundant in nearly all parts of the world except
          the arctic regions, and feed almost entirely on
          vegetation; a land snail.
      (b) Any gastropod having a general resemblance to the true
          snails, including fresh-water and marine species. See
          {Pond snail}, under {Pond}, and {Sea snail}.
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   2. Hence, a drone; a slow-moving person or thing.
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   3. (Mech.) A spiral cam, or a flat piece of metal of spirally
      curved outline, used for giving motion to, or changing the
      position of, another part, as the hammer tail of a
      striking clock.
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   4. A tortoise; in ancient warfare, a movable roof or shed to
      protect besiegers; a testudo. [Obs.]
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            They had also all manner of gynes [engines] . . .
            that needful is [in] taking or sieging of castle or
            of city, as snails, that was naught else but hollow
            pavises and targets, under the which men, when they
            fought, were heled [protected], . . . as the snail
            is in his house; therefore they cleped them snails.
                                                  --Vegetius
                                                  (Trans.).
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   5. (Bot.) The pod of the sanil clover.
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   {Ear snail}, {Edible snail}, {Pond snail}, etc. See under
      {Ear}, {Edible}, etc.

   {Snail borer} (Zool.), a boring univalve mollusk; a drill.

   {Snail clover} (Bot.), a cloverlike plant ({Medicago
      scuttellata}, also, {Medicago Helix}); -- so named from
      its pods, which resemble the shells of snails; -- called
      also {snail trefoil}, {snail medic}, and {beehive}.

   {Snail flower} (Bot.), a leguminous plant ({Phaseolus
      Caracalla}) having the keel of the carolla spirally coiled
      like a snail shell.

   {Snail shell} (Zool.), the shell of snail.

   {Snail trefoil}. (Bot.) See {Snail clover}, above.
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