cretaceous has definitions from the field of geology
1
[ adjective ] (geology) of or relating to the Cretaceous geologic era

Examples

"cretaceous rocks"

2
[ adjective ] abounding in chalk

Related terms

chalk

3
[ noun ] (geology) from 63 million to 135 million years ago; end of the age of reptiles; appearance of modern insects and flowering plants

Related terms

period Mesozoic

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