Simple Definition of ruler
: a person (such as a king or queen) who rules a country, area, group, etc.
: a straight piece of plastic, wood, or metal that has marks on it to show units of length and that is used to measure things
Examples of ruler in a sentence
a summit attended by a number of rulers from around the world
This ruler shows inches and centimeters.
First Known Use of ruler
RULER Defined for Kids
Definition of ruler for Students
1 : a person (as a king or queen) having supreme power over a nation
2 : a straight strip (as of plastic, wood, or metal) with a smooth edge that is marked off in units and used for measuring or as a guide in drawing straight lines
Seen and Heard
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