Polymorphism
A. The property of a programming language feature or entity being able to support multiple types of data.
Q. What is usually meant by function polymorphism?
A. The ability for one function to accept arguments whose types can vary from one call to another.
In Scheme, for example, CONS is polymorphic:
(cons 1 2) ; numeric arguments
(cons ’a ’b) ; symbolic arguments
Note: CONS is not overloaded; it's polymorphic.