Why is a manifold called a manifold? Manifold in English means many and various. (< How did this come to mean a topological manifold with a differentiable structure?

According to Aguirre, Foster, and Merali's _Questioning the Foundations of Physics_ , the term "manifold" comes from the German term "Mannigfaltigkeit" used by Riemann, which he used to describe the set of possible values of a variable under several constraints, because the variable can have many values. English mathematician and philosopher William Kingdon Clifford then translated this to "manifoldness."