nucleus ambiguus
noun
nucleus am·big·u·us
| \ -am-ˈbig-yə-wəs
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Medical Definition of nucleus ambiguus
: an elongated nucleus in the medulla oblongata that is a continuation of a group of cells in the ventral horn of the spinal cord and gives rise to the motor fibers of the glossopharyngeal, vagus, and accessory nerves supplying striated muscle of the larynx and pharynx