# ellipse

/ɪˈɫɪps/ (US) · /ɪlˈɪps/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/ellipse
Updated: 2026-10-13

## Definition

a shape like a long, flattened circle. You see this shape when you look at a circle from an angle or when you look at the path planets take around the sun.

For teachers: a regular oval shape, traced by a point moving in a plane so that the sum of its distances from two other points is constant.

## Examples

- The moon travels around the Earth in an ellipse.
- The architect designed the park's central fountain in the shape of a perfect ellipse to fit the narrow space.
- Kepler's first law of planetary motion states that the orbit of every planet is an ellipse with the Sun at one of the two foci.

## Synonyms

oval

## Usage notes

- Commonly used in geometry and astronomy to describe curved paths and symmetrical ovals.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.