homothety

9.9

To change a shape by making it all bigger or all smaller from the same center

noun
/ˌhɒməˈθɛti/

Specialized

: homotecia

A homothety with a ratio of 2 expands every point away from the center by a factor of two.

Examples

In geometry class, we learned that homothety preserves the shape but not the size of a figure.
The triangle was mapped onto itself by a homothety centered at the origin.
A homothety can be used to scale geometric figures.
The concept of homothety is fundamental in affine geometry.
A homothety with a ratio of 2 expands every point away from the center by a factor of two.
In geometry class, we learned that homothety preserves the shape but not the size of a figure.
The triangle was mapped onto itself by a homothety centered at the origin.

Synonyms

homothecy

vshomothety

Specialized

9.9

A change that makes a shape bigger or smaller from one center point

is the same mathematically but uses an alternate spelling form

Surface Forms

homothety singular

homotheties plural

Morphology

homothety = homo + thety

The combining form 'homo-' (meaning 'same') is recognizable to learners, but the element 'thety' is not a standalone English morpheme and the precise mathematical sense is specialized, so the meaning is only partially inferable.

Etymology

The word homothety comes from Greek parts homo- meaning 'same' and -thesis meaning 'placing'. So a homothety is a geometric change that keeps a figure's shape 'the same' while making it larger or smaller from a fixed center.