The name ' recorded by Ptolemy may be pre-Celtic. Islay is Ptolemy's , the use of the "p" hinting at a Brythonic or Pictish tribal name, , because the root is not Gaelic. Woolf (2012) has suggested that ' may be "an Irish attempt to reproduce the word ' phonetically rather than by translating it" and that the tribe's name may come from the root ' meaning "horse". Watson (1926) also notes the possible relationship between ' and the ancient Irish Ulaid tribal name ' and the personal name of a king recorded in the "Silva Gadelica".