The term 'Christian Name in Fashion' is a reference to the French fashion designer Christian Dior, whose four-letter last name is DIOR. Christian Dior was a renowned fashion designer who founded the House of Dior in 1946. He is credited with revolutionizing women's fashion and introducing the concept of the 'New Look' in 1947. His designs were known for their elegance and femininity, and he was one of the most influential fashion designers of the 20th century.