A person or animal that roars, especially one that is known for making loud, deep sounds. The lion, known as the king of the jungle, is a formidable roarer.
A device or machine that produces a loud roaring noise. The old furnace was a notorious roarer, making it difficult to hear anything else in the basement.
A person who is boisterous or noisy, often in a social setting. At the party, he was the life of the event, a real roarer with his loud jokes and laughter.
A horse that makes an abnormal roaring noise while breathing due to laryngeal paralysis (laryngeal hemiplegia). The veterinarian diagnosed the gelding as a roarer and recommended surgery to improve its breathing.