a deep prolonged loud noise

a very loud utterance (like the sound of an animal); "his bellow filled the hallway"

loud enough to cause (temporary) hearing loss

A whistling sound made by a horse during inhalation while exercising. It is caused by a partial or total paralysis of the nerves controlling the muscles which elevate the arytenoid cartilages which thereby open the larynx. In severe cases, a surgical procedure known as "tie-back surgery" (laryngoplasty) is performed, in which a suture is inserted through the cartilage to hold it out of the airway permanently. Paralysis almost exclusively occurs on the left side, most frequently in horses over 16 hands high.

Characteristic abnormal noise on inhalation, heard in horses with Laryngeal Hemiplegia.

Deep, prolonged cough, generally when a horse is galloping.