Cretaceous

krg-ta's hus, adj. composed of or like chalk. [L cretaccus, from creta, chalk.] Cretin, kre tin, n. one of a cla of idiot$ found in deep valleys, esp. among the Alps, and generally afflicted with goitre. [Ety. dub.] Cretinism, kre'tm-mn, « the condition of a cretin.