Definition
ostracoderm
noun
- An extinct jawless fish of the Paleozoic era, characterized by a bony or armored external covering.
Usage: paleontology; often used in plural form
Examples
- Ostracoderms were among the earliest vertebrates to appear in the fossil record.
- The ostracoderm's heavy armor plating provided protection in ancient seas.
- Scientists study ostracoderms to understand the evolution of early fish.
- Unlike modern fish, ostracoderms lacked true jaws for feeding.
- The discovery of ostracoderm fossils has helped paleontologists trace vertebrate ancestry.