Hilary Tann (born November 2, 1947, Llwynypia, Glamorgan, Wales, U.K.; died February 8, 2023, Schuylerville, New York), Welsh American composer, professor of music theory and composition at Union College, Schenectady, N.Y., and haiku poet. She was a founder of the Route 9 Haiku Group and its biannual anthology, Upstate Dim Sum. Cochaired the Haiku North America 2015 conference in Schenectady. Last resided in Schuylerville, N.Y.