Definition

1. Noun:

   • A prescribed guide for conduct or action; a regulation or principle governing procedure or behavior: An established standard or law that must be followed.
   • The exercise of authority or control; dominion: The power to govern or command.
   • A customary or habitual course of action: A usual practice or habit.
   • A straight-edged strip for measuring or drawing straight lines: A tool used in geometry or drafting.

2. Verb:

   • To exercise authority or power over; to govern or control: To have command over people or a territory.
   • To be prevalent or current: To be the standard or dominant condition.
   • To make a formal decision or judgment, especially in a legal context: To decide authoritatively.
   • To mark with lines using a ruler: To draw straight lines.

Usage Examples

• Noun:

  • Follow the rules of the game. (Obey the established guidelines for playing.)
  • The country was under foreign rule for decades. (The nation was controlled by a foreign power.)
  • As a rule, she drinks tea in the morning. (It is her usual habit.)
  • Use a rule to draw a straight line. (Use a measuring tool.)

• Verb:

  • A wise king should rule justly. (A wise king should govern with fairness.)
  • Chaos ruled in the streets after the storm. (Disorder was the prevailing condition.)
  • The judge will rule on the motion tomorrow. (The judge will make a legal decision.)
  • Rule the paper before you begin writing. (Draw lines on the paper.)

Advanced Usage

• "Rule of thumb": A practical, experience-based method or principle that is not strictly precise.

  • As a rule of thumb, cook the rice for 18 minutes. (Use this general, practical guideline.)

• "Rule out": To eliminate or exclude as a possibility.

  • The doctor ruled out an infection. (The doctor eliminated infection from consideration.)

• "Rule the roost": To be in charge or in a position of authority.

  • Everyone knows who rules the roost in that office. (Everyone knows who is in charge.)

Variants and Related Words

• Ruler (n): A person who governs; also, the measuring tool.

  • The ruler addressed the crowd. (The leader spoke.)
  • A 12-inch ruler. (A measuring stick.)

• Ruling (n/adj): An official decision; currently in power.

  • The court's ruling was final. (The court's decision.)
  • The ruling party. (The political party currently in control.)

Synonyms

• Noun: Regulation, law, principle, dominion, control, habit, custom.
• Verb: Govern, control, reign, dominate, decide, decree.

Related Phrasal Verbs

• Rule over: To have sovereignty or control over a place or people.

  • He ruled over a vast empire. (He governed a large empire.)

• Rule against/in favor of: To make a judicial decision opposing or supporting something.

  • The court ruled against the company. (The court decided unfavorably for the company.)

Related Idioms

• The exception proves the rule: The existence of an exception confirms that a general rule is valid.

  • He's usually late, so his being early today is the exception that proves the rule. (His punctuality today highlights his usual lateness.)

• Rule with an iron fist/rod: To govern in a very strict and harsh manner.

  • The dictator ruled with an iron fist. (The dictator governed with severe control.)

Noun

1. measuring stick consisting of a strip of wood or metal or plastic with a straight edge that is used for drawing straight lines and measuring lengths
2. (mathematics) a standard procedure for solving a class of mathematical problems
   • he determined the upper bound with Descartes' rule of signs
   • he gave us a general formula for attacking polynomials
3. a rule or law concerning a natural phenomenon or the function of a complex system
   • the principle of the conservation of mass
   • the principle of jet propulsion
   • the right-hand rule for inductive fields
4. any one of a systematic body of regulations defining the way of life of members of a religious order
   • the rule of St. Dominic
5. directions that define the way a game or sport is to be conducted
   • he knew the rules of chess
6. dominance or power through legal authority
   • France held undisputed dominion over vast areas of Africa
   • the rule of Caesar
7. the duration of a monarch's or government's power
   • during the rule of Elizabeth
8. a basic generalization that is accepted as true and that can be used as a basis for reasoning or conduct
   • their principles of composition characterized all their works
9. (linguistics) a rule describing (or prescribing) a linguistic practice
10. prescribed guide for conduct or action
11. something regarded as a normative example
    • the convention of not naming the main character
    • violence is the rule not the exception
    • his formula for impressing visitors
12. a principle or condition that customarily governs behavior
    • it was his rule to take a walk before breakfast
    • short haircuts were the regulation

Verb

1. keep in check
   • rule one's temper
2. mark or draw with a ruler
   • rule the margins
3. have an affinity with; of signs of the zodiac
4. decide on and make a declaration about
   • find someone guilty
5. be larger in number, quantity, power, status or importance
   • Money reigns supreme here
   • Hispanics predominate in this neighborhood
6. decide with authority
   • The King decreed that all firstborn males should be killed
7. exercise authority over; as of nations
   • Who is governing the country now?