alalia

The loss of the ability to speak, especially due to paralysis of the vocal cords.

A striking case of amnesic alalia was that of Lordat, a French physician, who thus described his malady: "I find myself deprived of the value of all words.[…]"

Speech delay, a delay in the development or use of the mechanisms that produce speech.

The other major exception, characters with Down syndrome (a condition that often includes among its symptoms alalia, or speech delay), are usually played by actors with Down syndrome[…].