The term “Old Master” is widely applied to distinguished European painters from the period between the 14th and 18th centuries. It is also used to refer to the artwork produced by these artists (oil paintings, tempera paintings, frescoes, drawings and prints). Web resources here and here.

Orazio Gentileschi. The Lute Player. Oil on canvas. Ca. 1612/1620. National Gallery of Art, Washington, DC.