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 blowout preventer is a large, specialized valve or similar mechanical device, used to seal, control and monitor oil and gas wells to prevent blowout, the uncontrolled release of crude oil and/or natural gas from a well. They are usually installed in stacks of other valves. Blowout preventers were developed to cope with extreme erratic pressures and uncontrolled flow emanating from a well reservoir during drilling. Kicks can lead to a potentially catastrophic event known as a blowout. In additi