Is it possible to override methods or properties in Dart language?

Yes, in Dart language, you can override methods and properties in subclasses.

To do this, you need to declare a method or getter/setter with the same name as in the base class in the subclass. It is recommended to use the @override annotation to explicitly indicate the override.

Example:

class Animal {
  void speak() {
    print('Animal sound');
  }

  String get name => 'Animal';
}

class Dog extends Animal {
  @override
  void speak() {
    print('Bark');
  }

  @override
  String get name => 'Dog';
}

void main() {
  var dog = Dog();
  dog.speak(); // Outputs: Bark
  print(dog.name); // Outputs: Dog
}

Thus, Dart supports overriding methods and properties to implement polymorphism.