[ krɪ'teɪʃəs ]
■ adjective Geology relating to or denoting the last period of the Mesozoic era (between the Jurassic and Tertiary periods, about 146 to 65 million years ago), a time when the first flowering plants appeared and at the end of which dinosaurs, ammonites, and many other organisms died out.
Origin
C17: from L. cretaceus (from creta 'chalk') + -ous .