a : something that is shaped by casting in a mould or kind: for example (1) : a reproduction (as of the statue) in metallic or plaster : casting (2) : a fossil copy of the details of a normal item by mineral infiltration b : an impact taken from an item having a site liquid or plastic material : mould They designed a mask from a wax cast of her encounter.
: a mass of plastic issue formed in cavities of diseased organs (given that the kidneys) and discharged from your body
discard indicates the letting go or throwing away of a thing that has become ineffective or superfluous while often not intrinsically valueless.