Female first name (English): Devon, Celtic (Geographic name as first name), use of the name of the county of Devon in England as a first name and the name of the county probably has a Celtic origin and comes from the name of a Celtic people, the Dumnonii, name both male Male and female in use first name (English): Devon, Celtic (Geographic name as first name), use of the name of the county of Devon in England as a first name and the name of the county probably has a Celtic origin and comes from the name of a Celtic people, the Dumnonii; name of both male and female in use