The Collaborative International Dictionary of English v.0.48:

Garter \Gar"ter\, n. [OE. gartier, F. jarreti[`e]re, fr. OF.
   garet bend of the knee, F. jarret; akin to Sp. garra claw,
   Prov. garra leg. See Garrote.]
   1. A band used to prevent a stocking from slipping down on
      the leg.
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   2. The distinguishing badge of the highest order of
      knighthood in Great Britain, called the Order of the
      Garter, instituted by Edward III.; also, the Order itself.
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   3. (Her.) Same as Bendlet.
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   Garter fish (Zool.), a fish of the genus Lepidopus,
      having a long, flat body, like the blade of a sword; the
      scabbard fish.

   Garter king-at-arms, the chief of the official heralds of
      England, king-at-arms to the Order of the Garter; -- often
      abbreviated to Garter.

   Garter snake (Zool.), one of several harmless American
      snakes of the genus Eut[ae]nia, of several species (esp.
      E. saurita and E. sirtalis); one of the striped
      snakes; -- so called from its conspicuous stripes of
      color.
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