Mathematics. the identity element of a group in which the operation is addition. (of a function, especially of a function of a complex variable) a point at which a given function, usually a function of a complex variable, has the value zero; a root.
Mucosa buccalis. The inner lining of the cheeks and lips, which is an anatomic region that includes all the mucous membrane lining of the inner surface of the cheeks and lips, from the line of contact of the opposing lips to the line of attachment of mucosa to the alveolar ridges and pterygomandibular raphe, which occupies an area of 50â60 cm2.
CS Lymph Nodes: Cheek (Buccal) Mucosa, Vestibule. 1  Note 1: For head and neck schemas, this field includes all lymph nodes defined as Levels I-VII and Other by AJCC.The complete definitions are provided in the General Instructions. Note 2: For head and neck schemas, additional information about lymph nodes (size of involved nodes, extracapsular extension, and levels involved) is coded in Site-Specific Factors 1-6. Note 3: If laterality of lymph nodes is not specified, assume nodes are ipsilateral.Midline nodes are considered ipsilateral.