rule
US /ruːl/
UK /ruːl/

1.
a statement of what may, must, or must not be done in a situation
:
•
The first rule of the club is to always be on time.
•
You must follow the safety rules.
2.
the exercise of ultimate power or authority over an area or group of people
:
•
The country was under military rule for many years.
•
The king's rule was just and fair.
1.