A constitution that requires a plebiscite or a referendum to be amended is

A constitution that requires a plebiscite or a referendum to be amended is called a "rigid" constitution. This means that the process of amending the constitution is deliberately made difficult and requires broad public support before changes can be made. A referendum or plebiscite is a way to involve the public in the decision-making process, ensuring that changes to the constitution have widespread support before they are enacted. The opposite of a rigid constitution is a "flexible" constitution, which can be amended through ordinary legislative processes without requiring a public vote.