Quant, Mary Syllabification: (Quant, Mary)Pronunciation: /kwänt/Definition of Quant, Mary (1934-), English fashion designer. She launched the miniskirt in 1966 and promoted bold colors and geometric designs. She was also one of the first to design for the ready-to-wear market. Quant, Mary in other Oxford dictionaries Definition of Quant, Mary in the British & World English dictionary