Rosalind Cecilia Hildegard Tanner (née Young) (1900–1992) was a mathematician and a historian of mathematics. She was the eldest daughter of the mathematicians Grace and William Young. She was born and lived in Göttingen in Germany (where her parents worked at the university) until 1908. During her life she used the name Cecily.Rosalind joined the University of Lausanne in 1917.