Courtesy of the National Institute on Deafness and other Communication Disorders
A complete language that utilizes “signs made by moving the hands combined with facial expressions and postures of the body,” according to the National Institute on Deafness and Other Communication Disorders. Many people in North America who are deaf or hard of hearing use it as a primary means of communication.
Specify American Sign Language on first reference, capitalizing all three words. ASL is acceptable on second reference.
REFERENCE: NCDJ Style Guide