terrapin \ter"rapin\, n. probably of american indian origin.
   zool.
   any one of numerous species of tortoises living in fresh and
   brackish waters. many of them are valued for food. written
   also terapin, terrapen, terrapene, turpen, and
   turapen.
   1913 webster

   note: the yellow-bellied terrapin pseudemys scabra of the
         southern united states, the red-bellied terrapin
         pseudemys rugosa or chrysemys rubriventris,
         native of the tributaries chesapeake bay called also
         potter, slider, and redfender, and the
         diamond-back or salt-marsh terrapin malaclemmys
         palustris, are the most important american species.
         the diamond-back terrapin is native of nearly the whole
         of the atlantic coast of the united states.
         1913 webster

   alligator terrapin, the snapping turtle.

   mud terrapin, any one of numerous species of american
      tortoises of the genus cinosternon.

   painted terrapin, the painted turtle. see under painted.
      

   speckled terrapin, a small fresh-water american terrapin
      chelopus guttatus having the carapace black with round
      yellow spots; -- called also spotted turtle.
      1913 webster
see also:
terapin terrapen terrapene turpen turapen pseudemys scabra 
pseudemys rugosa chrysemys rubriventris potter slider redfender 
malaclemmys palustris alligator terrapin mud terrapin cinosternon painted terrapin 
painted speckled terrapin chelopus guttatus spotted turtle 

tortoise \tor"toise\, n. oe. tortuce, fr. of. tortis crooked,
   fr. l. tortus twisted, crooked, contorted, p. p. of torquere,
   tortum, to wind; cf. f. tortue tortoise, ll. tortuca,
   tartuca, pr. tortesa crookedness, tortis crooked. so called
   in allusion to its crooked feet. see torture.
   1. zool. any one of numerous species of reptiles of the
      order testudinata.
      1913 webster

   note: the term is applied especially to the land and
         fresh-water species, while the marine species are
         generally called turtles, but the terms tortoise and
         turtle are used synonymously by many writers. see
         testudinata, terrapin, and turtle.
         1913 webster

   2. rom. antiq. same as testudo, 2.
      1913 webster

   box tortoise, land tortoise, etc. see under box,
      land, etc.

   painted tortoise. zool. see painted turtle, under
      painted.

   soft-shell tortoise. zool. see trionyx.

   spotted tortoise. zool. a small american fresh-water
      tortoise chelopus guttatus or nanemys guttatus
      having a blackish carapace on which are scattered round
      yellow spots.

   tortoise beetle zool., any one of numerous species of
      small tortoise-shaped beetles. many of them have a
      brilliant metallic luster. the larvae feed upon the leaves
      of various plants, and protect themselves beneath a mass
      of dried excrement held over the back by means of the
      caudal spines. the golden tortoise beetle cassida
      aurichalcea is found on the morning-glory vine and
      allied plants.

   tortoise plant. bot. see elephant's foot, under
      elephant.

   tortoise shell, the substance of the shell or horny plates
      of several species of sea turtles, especially of the
      hawkbill turtle. it is used in inlaying and in the
      manufacture of various ornamental articles.

   tortoise-shell butterfly zool., any one of several
      species of handsomely colored butterflies of the genus
      aglais, as aglais milberti, and aglais urticae, both
      of which, in the larva state, feed upon nettles.

   tortoise-shell turtle zool., the hawkbill turtle. see
      hawkbill.
      1913 webster
see also:
torture testudinata terrapin turtle testudo box tortoise 
land tortoise box land painted tortoise painted turtle 
painted soft-shell tortoise trionyx spotted tortoise chelopus guttatus 
nanemys guttatus tortoise beetle cassida aurichalcea tortoise plant elephant's foot 
elephant tortoise shell tortoise-shell butterfly aglais aglais milberti 
aglais urticae tortoise-shell turtle hawkbill