trilobite
/ˈtraɪləbaɪt/
noun
- A small extinct sea creature that lived hundreds of millions of years ago, with a hard shell and a body divided into three parts.
- Trilobites were one of the most successful early animals on Earth.
- While hiking, she found a rock with the imprint of a trilobite.
- The museum has a fossil of a trilobite that is over 400 million years old.