# dilation

/ˌdaɪˈɫeɪʃən/ (US) · /daɪlˈeɪʃən/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/dilation
Updated: 2026-05-19

## Definition

the act of making something larger or wider. In math, it means changing the size of a shape while keeping its shape the same.

For teachers: the process of increasing the size or extent of something. In a mathematical context, it refers to a transformation that scales an object from a fixed point without altering its shape.

## Examples

- The dilation of the pupil allows more light to enter the eye.
- The architect used a dilation of the original blueprint to create a larger model for the presentation.
- In topology, the dilation of a set by a certain radius involves adding all points within that distance to the original set, effectively expanding its boundary.

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