The term 'top layer' can be defined by three words: VENEER (6 letters), ARISTOCRACY (11 letters), and HEN (3 letters). VENEER is a thin layer of material applied to the surface of an object to give it a more attractive appearance. ARISTOCRACY is a form of government in which power is held by a small group of people from the highest social class. Finally, a HEN is a female bird, typically kept for laying eggs or for its meat. Together, these three words can be used to describe the top layer of something, whether it be a physical object, a social structure, or a species.