The word 饮食 is formed by combining two fundamental, pictographic characters representing essential human activities: 饮, which originally depicted a person bending over a vessel to drink, and 食, which depicted food gathered under a roof. By merging these two concrete, action-based concepts, "to drink" and "to eat", the compound naturally evokes the broader, abstract idea of "diet" or "food and drink" as a unified category of sustenance. It is a conceptual fusion where two specific parts create a holistic whole.