Concrete Class

noun

say it: “KON-kreet klas” /ˈkɒŋkriːt klæs/

A complete class you can create objects from, with a body for every method.

What is Concrete Class?

Concrete Class — A complete class you can create objects from with new. Every method has a body, including the ones it inherits as abstract and has to fill in. An abstract class is the opposite: a partial design you can only inherit from.

abstract class Shape { public abstract double Area(); }
class Circle(double radius) : Shape          // concrete
{
    public override double Area() => Math.PI * radius * radius;
}

In a sentence

• “Circle is a concrete class, so new Circle(2) works, but new Shape() doesn't.”

Level: Journeyman · More OOP terms at this level

Updated October 28, 2026