The geniohyoid muscle is a small, thin muscle located in the neck. It originates at the genial tubercle, a small projection on the inner surface of the mandible (jawbone), and extends downward and forward to insert into the hyoid bone, a U-shaped bone located in the neck. The geniohyoid muscle is part of a group of muscles called the infrahyoid muscles, which are located below the hyoid bone and play a role in moving the hyoid bone and the mandible during swallowing and speaking.

The geniohyoid muscle has several important functions in the head and neck. It helps to lift the hyoid bone and the mandible during swallowing, and is also involved in the production of speech sounds. It also helps to support the floor of the mouth and the tongue, and can assist in keeping the airway open during respiration.

The geniohyoid muscle is innervated by the hypoglossal nerve, which is a cranial nerve that controls the muscles of the tongue. It is a voluntary muscle, meaning that it can be controlled voluntarily by the person.

In some cases, the geniohyoid muscle may be surgically modified or altered to address certain medical conditions, such as problems with swallowing or speaking. It may also be used as a donor muscle for reconstructive surgery in the head and neck region.