Poisson's ratio

or Poisson ratio

noun

, Physics.

1. the ratio, in an elastic body under longitudinal stress, of the transverse strain to the longitudinal strain.

Poisson's ratio

noun

1. a measure of the elastic properties of a material expressed as the ratio of the fractional contraction in breadth to the fractional increase in length when the material is stretched μν

Word History and Origins

Origin of Poisson's ratio¹

First recorded in 1925–30; Poisson distribution

Example Sentences

The behavior of elastic materials is partially described by Poisson's ratio, which explains how the material changes shape when you stretch or squeeze it in one direction.

From Science Daily

Most materials have a positive Poisson's ratio, which means squeezing them in one direction will make them wider and/or thicker in other directions.

From Science Daily

Auxetics have a negative value of Poisson's ratio and do exactly the reverse.

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Another way of expressing Poisson's ratio is that it describes the relationship between shape and volume when one of these changes.

From Science Daily

The digitally programmable material exhibits remarkable mechanical capabilities, including shape-shifting and memory, stress-strain response, and Poisson's ratio under compressive load.

From Science Daily