Immutable and Rigid

Immutable adjective - Not capable of changing or being changed.

Rigid is a synonym for immutable in flexible topic. In some cases you can use "Rigid" instead an adjective "Immutable", when it comes to topics like unchangeable.

Nearby Word: immutability

Rigid adjective - Not allowing for any exceptions or loosening of standards.

Immutable is a synonym for rigid in fixed topic. Sometimes you can use "Immutable" instead an adjective "Rigid", if it concerns topics such as flexible.

Nearby Words: rigor, rigidity, rigidly