Origin: Latin suffix -ous
Cretaceous has 5 different meanings across 3 categories:
Noun · Adjective · Proper Noun
from 135 million to 63 million years ago; end of the age of reptiles; appearance of modern insects and flowering plants
abounding in chalk
of or relating to or denoting the third period of the Mesozoic era
Of or relating to chalk.
The geologic period within the Mesozoic era that comprises lower and upper epochs from about 146 to 66 million years ago.