'arthur' originates from Latin, specifically the word 'Arthurus', where the name is thought to reflect either the Roman family name 'Artorius' or the Celtic element 'artos' meaning 'bear'.

'arthur' changed from medieval Latin 'Arthurus' and Old Welsh/Brythonic 'Arthur' (and possibly from the Roman name 'Artorius'), and eventually became the modern English proper name 'Arthur'.

Initially associated with a personal or family name (possibly linked to 'bear'), over time it became strongly identified with the legendary British king 'Arthur' and the cultural cycle of stories about him.