The Brythonic languages (or Brittonic languages) form one of the two branches of the Insular Celtic language family, the other being Goidelic. The name Brythonic is derived from the Welsh word Brython, meaning an indigenous Briton as opposed to an Anglo-Saxon or Gael. The Brythonic branch is also referred to as P-Celtic because the Brythonic reflex of the Proto-Indo-European phoneme *kw is p as opposed to the Goidelic c. Such nomenclature usually implies an acceptance of the P-Celtichypothesis rather than the Insular Celtic hypothesis (for a discussion, see Celtic languages).
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