Vaire the Weaver is called this for her weaving of tapestries depicting all things that are in Time, past, present, and future. These are hung all about the ever-widening Halls of Mandos, in which she lives with her husband, Namo Mandos.
Reference: "Valaquenta", Silmarillion
"Vaire". Artist: Olga Kukhtenkova. Rolozo Tolkien page