Violet Stewart Louisa Piercy (24 December 1889 – April 1972) was an English long-distance runner who is recognized by the International Association of Athletics Federations as having set the first women's world best in the marathon on 3 October 1926 with a time of 3:40:22. Piercy was reported to have run unofficially and her mark was set on the Polytechnic Marathon course between Windsor and London.
According to the IAAF, Piercy's mark stood 37 years until Merry Lepper's 3:37:07 performance at the Western Hemisphere Marathon on 16 December 1963.
Piercy died in April 1972 in a London hospital after suffering a brain haemorrhage, hypertension and chronic kidney-related infection. The death certificate mistakenly gave her surname as Pearson.