To represent an abstract concept by a concrete or tangible example. The artist instantiated the concept of freedom through her sculpture.
To create an instance of a class in object-oriented programming. The programmer instantiated a new object from the class to test its methods.
In logic or mathematics, to replace a variable with a specific value or term, thereby producing a concrete instance of a general statement. Instantiating the variable x with 3 turns the formula x + 2 = 5 into the concrete equation 3 + 2 = 5.