A group of muscles lying superficially on a structure, in contrast to intrinsic muscles, which are located deeply
For instance, the extrinsic muscles of the tongue include genioglossus muscle, hyoglossus muscle, styloglossus muscle, and palatoglossus muscle. Since they are extrinsic muscles, they are located on the surface of the tongue, and attach the tongue to other structures. They all insert into the tongue but have differing origins. Genioglossus muscle originates from the mandible, the hyoglossus muscle is from the hyoid bone, styloglossus muscle from the styloid process, and palatoglossus muscle from the palatine aponeurosis.