Cambrian

adjective

Cam·​bri·​an ˈkam-brē-ən  ˈkām- 

1

: welsh

2

: of, relating to, or being the earliest geologic period of the Paleozoic era or the corresponding system of rocks marked by fossils of nearly every major invertebrate animal group see Geologic Time Table

Cambrian noun

Examples of Cambrian in a Sentence

Recent Examples on the Web

Then there was the transition to multicellular organisms (around 2 billion to 1.6 billion years ago), the abrupt diversification of body forms in the Cambrian explosion (540 million years ago), and the appearance of central nervous systems (around 600 million to 520 million years ago). —Quanta Magazine, 2 Apr. 2025

By 540 million years ago, the Cambrian explosion was underway — a rapid diversification of life that saw the emergence of complex multicellular organisms, predatory behavior and the foundations of modern ecosystems. —Scott Travers, Forbes.com, 30 Mar. 2025

But that Cambrian explosion, when the animals start to figure out all these evolutionary innovations, that’s later, right? —Steven Strogatz, Quanta Magazine, 20 Mar. 2025

Other mysteries include how biological cells first evolved, and what caused the dramatic onset of complex life during the Cambrian explosion 540 million years ago. —Keith Cooper, Space.com, 21 Feb. 2025

Word History

Etymology

Medieval Latin Cambria Wales, from Middle Welsh Cymry Wales, Welshmen

First Known Use

1603, in the meaning defined at sense 1

Rhymes for Cambrian

• precambrian

Kids Definition

Cambrian

adjective

Cam·​bri·​an ˈkam-brē-ən  ˈkām- 

: of, relating to, or being the earliest period of the Paleozoic era of geological history or the corresponding system of rocks marked by fossils of nearly every major invertebrate animal group see geologic time

Cambrian noun