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# perimeter

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noun pe·rim·e·ter \pə-ˈri-mə-tər\

## Simple Definition of perimeter

• : the outside edge of an area or surface

• : the total length of the lines that form a shape

• the perimeter basketball : the area on a basketball court that is not close to the basket

Source: Merriam-Webster's Learner's Dictionary

## Full Definition of perimeter

1. 1 a :  the boundary of a closed plane figure b :  the length of a perimeter

2. 2 :  a line or strip bounding or protecting an area

3. 3 :  outer limits —often used in plural

4. 4 :  the part of a basketball court outside the three-point line

## Examples of perimeter in a sentence

1. He scored from the perimeter.

2. <soldiers guarding the perimeter of the camp>

## Origin and Etymology of perimeter

Middle English perimetre, from Latin perimetros, from Greek, from peri- + metron measure — more at measure

First Known Use: 15th century

## perimeter

play
noun pe·rim·e·ter \pə-ˈri-mə-tər\

## Definition of perimeter for Students

1. 1 :  the whole outer boundary of a figure or area

2. 2 :  the length of the boundary of a figure

## Word Root of perimeter

The Greek word metron, meaning “measure,” gives us the root metr. Words from the Greek metron have something to do with measuring. A thermometer is an instrument that measures temperature. A diameter is the measurement across the center of a circle. The metric system is a system used for measuring size, weight, and volume. A perimeter is the measurement of the outside of a figure or shape.

## perimeter

play
noun pe·rim·e·ter \pə-ˈrim-ət-ər\

## Medical Definition of perimeter

1. 1a:  the boundary of a closed plane figureb:  the length of a perimeter

2. 2:  an instrument for examining the discriminative powers of different parts of the retina often consisting of an adjustable semicircular arm with a fixation point for the eye and variable stations for the visual stimuli

## Seen and Heard

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#### littoral

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of, relating to, or near a shore

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