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 of ruler

• monarch
• emperor
• sovereign
• king

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

Woody and Buzz have survived sadistic neighbors, evil toys and tyrannical daycare rulers. — Rachel Hale, USA Today, 26 June 2026

Jones said Shiite rulers in several South Asian kingdoms sponsored processions and other commemorations of Hussein’s martyrdom, helping turn them into public events that drew wider audiences. — ABC News, 25 June 2026

These new rulers were keen to sell themselves as legitimate successors to the emperors, and there was considerable continuity during this turbulent period. — Literary Hub, 25 June 2026

Democracies are composed of citizens with free will, not subjects cowering at the feet of rulers. — Jeffrey Sonnenfeld, Fortune, 24 June 2026

Word History

First Known Use

14th century, in the meaning defined at sense 1

Phrases Containing ruler

• co-ruler

Rhymes for ruler

• cooler
• 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