Mute (disorder)
Muteness was the inability to speak due to dysfunction of the larynx or as a result of a psychological condition that caused a person to become unable to speak due to trauma or shock. It frequently accompanied deafness. ()

The inhabitants of Gamma Vertis IV were all naturally mute, as was Gem. ()

The ruling family of Ramatis III all shared a genetic condition rendering them deaf and mute. One member of the ruling family, the famed mediator Riva, overcame his condition by using a chorus of telepathic aides to speak on his behalf. ()

The two Bajoran farmers Baltrim and Keena were rendered mute during the Cardassian Occupation of Bajor. ()

In 2372, Chancellor Gowron called Worf a mute d'blok. ()

External link 
 
Medical conditions