n. pl. tuatara or tu·a·ta·ras
Either of two lizardlike reptiles (Sphenodon punctatus or S. guntheri) that inhabit several small New Zealand islands and are the only extant members of the group Rhynchocephalia or Sphenodontia, which flourished during the Mesozoic Era. Also called sphenodon.
[Maori tuatara : tua, back + tara, spine.]
(click for a larger image)tuatara
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Indo-European & Semitic Roots Appendices
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