Greyhound (noun)

1. A tall, slender breed of dog with a narrow head, long legs, and a short, smooth coat, used for racing and hunting.
2. A person or thing that is fast and agile.

Origin:

Old english grighund, of unknown origin. the grey part may have been influenced by an old norse word meaning "old" or "gray", or by a celtic word for "dog".

Examples:

1. He had always been fascinated by greyhounds, with their slender and elegant bodies.
2. The greyhound is a very fast breed of dog, and is often used in racing.
3. She was a greyhound of a woman, always on the go and always in a hurry.
4. The greyhound chased after the rabbit, but it was too fast for him.
5. The greyhound bus service is known for being fast and efficient.