ruler

noun

rul·​er ˈrü-lər 

1

: one that rules

specifically : sovereign

2

: a worker or a machine that rules paper

3

: a smooth-edged strip (as of wood or metal) that is usually marked off in units (such as inches) and is used as a straightedge or for measuring

rulership

ˈrü-lər-ˌship 

noun

Synonyms

• autocrat
• monarch
• potentate
• sovereign
• sovran

Examples of ruler in a Sentence

a summit attended by a number of rulers from around the world

This ruler shows inches and centimeters.

Recent Examples on the Web

The dynastic rulers in the French House of Bourbon, unlike the rulers in Britain, did not cede power voluntarily; Robespierre and the Jacobins took it from them violently in the French Revolution. —Robert D. Atkinson, National Review, 9 Apr. 2025

Huge Tomb of Unknown Pharaoh Found: The burial chamber in Egypt most likely belonged to a ruler in a line of kings once lost to history, researchers said. —Noriko Hayashi, New York Times, 8 Apr. 2025

With your celestial ruler, Mercury, back to basics, especially in your 10th house of boss moves and public persona, everything from the trajectory of your career to your sense of authority takes center stage. —Valerie Mesa, People.com, 7 Apr. 2025

The emoluments clause is a provision of the U.S. Constitution (Article I, Section 9, Paragraph 8) that generally prohibits federal officeholders from receiving any gift, payment or other thing of value from a foreign state or its rulers, officers, or representatives. —Rosemary Feitelberg, Footwear News, 7 Apr. 2025

Word History

First Known Use

14th century, in the meaning defined at sense 1

Phrases Containing ruler

• co-ruler

Rhymes for ruler

• cooler
• jeweller
• schooler
• schuller
• preschooler
• vestibular

Kids Definition

ruler

noun

rul·​er ˈrü-lər 

1

: sovereign entry 1 sense 1

2

: a straight strip of material (as wood or metal) marked off in units and used as a guide in drawing lines or for measuring