The hyoid bone is a very special bone in the human head which is unique in that it is not attached to any other bones in the body; rather, it is supported by a network of muscles and ligaments, which trap it like a fly in amber directly below the tongue. The primary role of the bone is to support the weight of the tongue, allowing people to articulate words while speaking, and enabling the production of a wide range of vocalizations.
Without the hyoid bone, humans would be incapable of speech as we know it, so this bone represents a major step in human evolution. The first hyoid bones appeared in hominids around 300,000 years ago, and they were accompanied by a phenomenon known as the larynx drop, which allows the larynx to settle deeper into the throat after childhood, further enabling speech. Needless to say, we probably wouldn't exist in our current state without this bone, as speech is a crucial tool for civilization.
This bone is shaped roughly like a horseshoe, and it nestles in the throat below the tongue. This bone is also sometimes called the "lingual bone," in a references to the fact that it gives humans the power of speech. The term "hyoid" comes from the Greek hyoeides, which means "upsilon-shaped." The Greek letter upsilon is shaped much like the Roman letter U.
When looking at the hyoid bone, it can be broken into several sections. The main "body" is like the heavy base of the U, while the greater cornu are the horns which make up the arms of the U. The lesser cornu are two smaller sections of the hyoid which create a second set of horns on the U, near the body of the hyoid bone.
In addition to being of interest to living humans, the bone is also sometimes important in forensic analysis. When the hyoid bone is broken, it is a strong indicator that someone was strangled, as the bone is otherwise extremely difficult to break. Therefore, forensic analysts often check on the condition of the hyoid in a suspicious death, especially in the event that only skeletal remains are available for autopsy, as a broken hyoid can seal the deal, as it were, providing evidence of a clear case of strangulation.