The Collaborative International Dictionary of English v.0.48:

Reptile \Rep"tile\ (r?p"t?l;277), a. [F. reptile, L. reptilis,
   fr. repere, reptum, to creep; cf. Lith. reploti; perh. akin
   to L. serpere. Cf. Serpent.]
   1. Creeping; moving on the belly, or by means of small and
      short legs.
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   2. Hence: Groveling; low; vulgar; as, a reptile race or crew;
      reptile vices.
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            There is also a false, reptile prudence, the result
            not of caution, but of fear.          --Burke.
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            And dislodge their reptile souls
            From the bodies and forms of men.     --Coleridge.
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The Collaborative International Dictionary of English v.0.48:

Reptile \Rep"tile\, n.
   1. (Zool.) An animal that crawls, or moves on its belly, as
      snakes,, or by means of small, short legs, as lizards, and
      the like.
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            An inadvertent step may crush the snail
            That crawls at evening in the public path;
            But he that has humanity, forewarned,
            Will tread aside, and let the reptile live.
                                                  --Cowper.
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   2. (Zool.) One of the Reptilia, or one of the Amphibia.
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   Note: The amphibians were formerly classed with Reptilia, and
         are still popularly called reptiles, though much more
         closely allied to the fishes.
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   3. A groveling or very mean person.
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WordNet (r) 3.0 (2006):

reptile
    n 1: any cold-blooded vertebrate of the class Reptilia including
         tortoises, turtles, snakes, lizards, alligators,
         crocodiles, and extinct forms [syn: reptile, reptilian]