Old South Arabian (or
Epigraphic South Arabian, or
Ṣayhadic) is a group of four closely related extinct languages spoken in the far
southern portion of the
Arabian Peninsula. There were a number of other Old South Arabian languages (e.g. Awsānian), of which very little evidence has survived, however. A sole surviving Sayhadic language is attested at
Jabal Rāziḥ in far north-west of
Yemen, though the varieties of speech in neighboring areas have both Arabic and Sayhadic features, and it is difficult to classify them as either Arabic dialects with a Sayhadic substratum, or Sayhadic languages that have been restructured under pressure of Arabic.