Oilcake

Part of speech: noun

Definitions

1. A solid material left after extracting oil from seeds or nuts, frequently employed as a source of protein in animal feed
2. The residue obtained from plants after the oil extraction process, often used to enhance livestock diets
3. A byproduct resulting from the oil extraction of seeds or nuts that serves as a protein-rich feed ingredient for livestock

Etymology: Oilcake is about as transparent as English compounds get: "oil" plus "cake." The "cake" here is the pressed solid left behind after seeds or nuts have been crushed to squeeze out their oil. Once the oil is gone, what remains is a dense, flat slab, and because it is still rich in protein it has long been fed to cattle, sheep and other livestock. The sense of "cake" is older than the modern meaning of sweet baked goods, which suggests that the broader idea of a flattened, pressed mass came first. Oilcake is therefore a literal description of the product, not a metaphor: the compound names the material as a pressed cake that has yielded its oil.