If a government or other elected body has a mandate to carry out a particular policy or task, they have the authority to carry it out as a result of winning an election or vote.

If someone is given a mandate to carry out a particular policy or task, they are given the official authority to do it.

You can refer to the fixed length of time that a country's leader or government remains in office as their mandate .

When someone is mandated to carry out a particular policy or task, they are given the official authority to do it.

To mandate something means to make it mandatory.