Sentence:  The red dragon had already been in intermittent use for centuries as a device for a general, a <WSD>pen-dragon</WSD>, a 'head-leader' in Celtic, and it was strongly associated with the name of w:Cadwaladr 
Meaning of the word marked with <WSD> tags:  "Also capitalized as" '''(Pendragon)''': (title assumed by the ancient British chiefs when called to lead other chiefs): chief war leader, chieftain, dictator, despot or king.