Lexical NMS

Non-manual signs that are an integral part of a specific sign's production, required to distinguish it from other signs that share the same manual component. For example, the ASL sign for "NOT YET" includes a hand gesture combined with the tongue touching the lower lip and a head rotation; without these NMS, the sign could be misunderstood as "LATE." Lexical NMS are part of the phonological structure of individual signs and must be learned as part of each sign's form, making them particularly challenging for hearing learners who may not realize a sign has a required facial component.