the.com/cereal

means A processed grain food, typically eaten with milk at breakfast, ranging from flakes to puffs to sugary shapes.

from From Latin 'Cerealis,' meaning 'of Ceres,' the Roman goddess of agriculture and grain harvests. The word entered English in the 1800s as a term for grain crops generally (wheat, oats, barley), and only narrowed to mean 'breakfast food in a box' once companies in the late 19th century began selling pre-processed grains as a quick morning meal — turning a goddess's harvest into something you pour from a cardboard box.