A ductile element is an element on the periodic table that is high ductile. A highly ductile element is able to deform when tensile stress is applied, which means to ends are being pulled apart. In general, transition metals are the most ductile element, which are the metals in columns three to 38 on the table.
Some examples of ductile elements are nickel, copper, silver and gold. Ductility is important if a material is going to be exposed to significant tensile stress. If a material isn't ductile, it may just fracture when stress is applied. Malleability is a similar property, which is the ability to deform when compressive stress is applied.