Turtle

n. reptile with a hard shell around the trunk of the body (living in freshwater, saltwater, or on land); turtle flesh; (Nautical) pocket in a spinnaker (large triangular sail)

Turtles, Tortoises, and Terrapins are reptiles of the Order Testudines (all living turtles belong to the crown group Chelonia), most of whose body is shielded by a special bony or cartilaginous shell developed from their ribs. The Order Testudines includes both extant (living) and extinct species, the earliest known turtles being from around 215 million years ago, making turtles one of the oldest reptile groups, and a much more ancient group than lizards and snakes. About 300 species are alive today; some are highly endangered.
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Noun
1. any of various aquatic and land reptiles having a bony shell and flipper-like limbs for swimming
(hypernym) chelonian, chelonian reptile
(hyponym) sea turtle, marine turtle
(part-meronym) carapace, shell, cuticle
Verb
1. overturn accidentally; "Don't rock the boat or it will capsize!"
(synonym) capsize, turn turtle
(hypernym) overturn, turn over, tip over, tump over
2. hunt for turtles, especially as an occupation
(hypernym) hunt, run, hunt down, track down
(derivation) turtler

v. coo, make soft cooing sounds, talk amorously

(n.)
The turtledove.
  

(n.)
The curved plate in which the form is held in a type-revolving cylinder press.
  

(n.)
Any one of the numerous species of Testudinata, especially a sea turtle, or chelonian.