The muscular structure located beneath the lower lip is called "musculus triangularis labii inferioris". It is pronounced as /ˈmʌskjʊləs traɪˈæŋɡjʊlərɪs ˈleɪbi ɪnˈfɪərɪs/ in IPA phonetic transcription. The word is derived from Latin and refers to its triangular shape and its location beneath the lower lip. The correct spelling of this word can be a challenge due to the many syllables and unique vowel sounds. However, with the use of IPA transcription, the pronunciation can be understood more easily.
Musculus Triangularis Labii Inferioris is a Latin term used in anatomy and biology to refer to a specific muscle in the human face. The word "musculus" means muscle in Latin, "triangularis" refers to the triangular shape of the muscle, "labii" signifies its attachment to the lips, and "inferioris" indicates its location lower in the face.
The Musculus Triangularis Labii Inferioris, also known as the depressor anguli oris, is a thin, flat muscle found on each side of the lower lip. It arises from the mandible (lower jawbone) near the midline and then expands radially to form a triangular shape, with the apex pointing downwards towards the chin. This muscle plays a crucial role in facial expressions and lip movements.
When the Musculus Triangularis Labii Inferioris contracts, it pulls the corner of the mouth downward and laterally, causing a frown or expression of sadness. Conversely, its relaxation allows the lips to return to a neutral position or perform other movements like smiling.
The Musculus Triangularis Labii Inferioris is part of the complex network of muscles that allows for facial expressions and contributes to non-verbal communication. It works in coordination with other muscles around the mouth, such as the orbicularis oris, to produce a wide range of movements necessary for speech, eating, and expressing emotions.
M. depressor anguli oris, m. triangularis.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.