Meaning: Membranous structure that functions as the circulatory system in mammal embryos until the heart becomes functional. Classified under: Nouns denoting animals. Synonyms: umbilical vesicle; vesicula umbilicus; vitelline sac; yolk sac. Hypernyms (vesicula umbilicus is a kind of...): sac (a structure resembling a bag in an animal)
electric fan; blower. Hypernyms (blower is a kind of...): fan (a device for creating a current of air by movement of a surface or surfaces) Meronyms (parts of blower): electric motor (a motor that converts electricity to mechanical work) fan blade (blade of a rotating fan)
A system of valves or baffles, or both, is usually incorporated to simultaneously operate a small radiator inside the vehicle. This small radiator, and the associated blower fan, is called the heater core, and serves to warm the cabin interior. Like the radiator, the heater core acts by removing heat from the engine.