Sanction

A sanction may be either a permission or a restriction, depending on context, as the word is an auto-antonym.

Examples of sanctions include:

Involving countries:

• economic sanctions, typically a ban on trade, possibly limited to certain sectors (such as armaments), or with certain exceptions (such as food and medicine) like sanctions against Iran
• international sanctions, coercive measures adopted by a country or a group of countries against another state or individual(s) in order to elicit a change in their behavior
• pragmatic sanction, historically, a sovereign's solemn decree which addresses a matter of primary importance and which has the force of fundamental law

In other uses:

• sanctions (law), penalties imposed by courts
• sanctions, mechanisms of social control
• sanctioned name, a special name in mycology