- 1. Angle or corner of the eye, lips, or labia. 2. A bundle of nerve fibers passing from one side to the other in the brain or spinal cord. SYN: commissura [TA].- anterior c. [TA] a round bundle of nerve fibers that crosses the midline of the brain near the anterior limit of the third ventricle. It consists of a smaller anterior part (pars anterior commissurae anterioris [TA]), the fibers of which pass in part to the olfactory bulbs, and a larger posterior part (pars posterior commissurae anterioris [TA]), which interconnects the left and right temporal lobes. SYN: commissura anterior [TA].- anterior labial c. [TA] the junction of the labia majora anteriorly at the mons pubis. SYN: commissura labiorum anterior [TA].- c. of bulbs [TA] a narrow median band that connects the two masses of erectile tissue (the bulbus vestibuli) on either side of the vaginal orifice. SYN: commissura bulborum [TA], c. of vestibular bulb, intermediate part of vestibular bulb, pars intermedia commissurae bulborum.- c. of cerebral hemispheres SYN: corpus callosum.- c. of fornix [TA] SYN: commissura fornicis.- gray c. [TA] narrow bands of gray substance spanning the midline dorsal to the central canal (posterior gray c. [TA], commissura griesa posterior [TA]) and ventral to the central canal (anterior gray c. [TA], commissura grisea anterior [TA])- c. of habenulae SYN: commissura habenularum.- habenular c. [TA] SYN: commissura habenularum.- hippocampal c. SYN: commissura fornicis.- c. of inferior colliculus [TA] nerve fibers on the midline between the two inferior colliculi connecting the colliculi and containing some fibers originating from nontectal nuclei.- labial c. [TA] junction of upper and lower lip which occurs at corner of mouth. SEE ALSO: angle of mouth.- lateral palpebral c. [TA] the union of the upper and lower eyelids adjacent to the lateral angle. SYN: commissura lateralis palpebrum [TA], commissura palpebrarum lateralis.- c. of lips the junction of the lips lateral to the angle of the mouth. SYN: commissura labiorum [TA], junction of lips.- medial palpebral c. [TA] the union of the upper and lower eyelids adjacent to the medial angle. SYN: commissura medialis palpebrum [TA], commissura palpebrarum medialis.- posterior labial c. [TA] a slight fold uniting the labia majora posteriorly in front of the anus. SYN: commissura labiorum posterior [TA].- c. of superior colliculus [TA] nerve fibers interconnecting corresponding and noncorresponding portions of the two superior colliculi across the midline; may contain fibers originating outside the tectum. SYN: brachium colliculi superioris [TA].- Wernekinck c. the decussation of the brachia conjunctiva before their entrance into the red nucleus of the tegmentum.- white c. a narrow band of white matter that crosses the midline of the spinal cord dorsal to the central canal and posterior gray c. (posterior white c. [TA]) and ventral to the central canal and the anterior gray c. (anterior white c. [TA]). SYN: anterior white c. [TA], commissura alba anterior [TA], commissura alba posterior [TA], ventral white column [TA], ventral white c. [TA], commissura ventralis alba.
* * *com·mis·sure 'käm-ə-.shu̇(ə)r n1) a point or line of union or junction between two anatomical parts (as the lips at their angles or adjacent heart valves)2) a connecting band of nerve tissue in the brain or spinal cord see ANTERIOR COMMISSURE, CORPUS CALLOSUM, GRAY COMMISSURE, HABENULAR COMMISSURE, HIPPOCAMPAL COMMISSURE, POSTERIOR COMMISSURE compare MASSA INTERMEDIAcom·mis·su·ral .käm-ə-'shu̇r-əl adj
* * *n.1. a bundle of nerve fibres that crosses the midline of the central nervous system, often connecting similar structures on each side.2. any other tissue connecting two similar structures.
* * *com·mis·sure (komґĭ-shər) 1. a site of union of corresponding parts; see also commissura. 2. the site of junction between adjacent cusps of a heart valve.
Medical dictionary. 2011.