A roar is a deep, bellowing outburst of sound forced through an open mouth. It is produced by animal

Animal

Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

s of certain species. A roar is usually made using hyoid

Hyoid bone

The hyoid bone is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies at the level of the base of the mandible in the front and the third cervical vertebra behind.Unlike other bones, the hyoid is only distantly...

, a small bone which is not completely rigid in adults. Animals roar for various reasons, including territorial proclamation, communication with other members, and anger.