rule
Official instruction or law
A statement that says what you must or must not do.
a rule about [something]
- The school has a rule against using phones in class.
- New safety rules were introduced after the accident.
- You must follow the rules if you want to play the game.
- There is a rule about wearing shoes in the gym.
- We have a new rule at home.
- Please follow the rules in the library.
Govern or control people/places
To control a place or people as a leader.
to rule [a place]
- The king ruled the land for fifty years.
- They ruled the city until they were overthrown.
- She ruled the empire wisely and fairly.
- The queen rules the country.
- He ruled the small island for many years.
- They rule the city together.
General principle or guideline
A fact or idea that is usually true in most situations.
- As a general rule, you should back up your data regularly.
- The rules of grammar help us write correctly.
- There are exceptions to every rule.
- As a rule, I drink tea in the morning.
- The rules of math are important.
- There are rules for writing English sentences.
Make an official legal decision
To make an official decision about something important, often in court.
to rule that [clause]
- The judge ruled in favor of the defendant.
- The court ruled that the law was unconstitutional.
- They ruled against the proposal after much debate.
- The judge ruled that he was not guilty.
- The court ruled against him.
- The school ruled that hats are not allowed.
Straight-edged measuring tool
A flat tool with numbers used to measure length or draw straight lines.
- He measured the paper with a steel rule.
- Use a rule to draw the diagram accurately.
- The carpenter kept his rule in his pocket.
- I use a rule to draw lines.
- The rule is 30 centimeters long.
- She measured it with a rule.
- Base: rule
- Plural: rule, rules
- Base: rule
- 3rd Person Singular: rules
- Present Participle: ruling
- Past: ruled
as a rule
1Generally true in most cases
Usually; in most situations.
- As a rule, we don’t eat after 9 p.m.
- As a rule, children love playing outside.
lay down the law/rules
1State rules firmly to others
To tell people clearly and strongly what they must do.
- The teacher laid down the rules on the first day of class.
- He laid down the law about no smoking inside.
rule out
1Exclude something as an option
To decide that something is not possible or will not happen.
- The police have ruled out robbery as a motive.
- We can’t rule out the possibility of rain.
rule the roost
1Be in charge of everything
To be the person who makes all the decisions in a group or place.
- She really rules the roost at home.
- In this office, it's clear who rules the roost.
rule of thumb
1general practical guideline
A simple general rule that people use in normal life, not a strict or exact rule.
- As a rule of thumb, you should save at least ten percent of your income.
- A good rule of thumb is to add one extra minute of cooking time for every hundred watts less power.
rule of thumb
2Practical general guideline
A simple way to judge or decide something based on experience, not exact facts.
- As a rule of thumb, add two minutes for each extra kilometer.
- A good rule of thumb is to save 10% of your income.