# koi

Source: https://englishreference.com/word/koi
Updated: 2026-08-27

## Senses

### 1. ornamental fish

noun · CEFR B2

a large, colourful type of fish that people keep in garden ponds for decoration.

For teachers: ornamental domesticated varieties of the Amur carp, originally from East Asia, bred for specific colours and patterns.

- The garden had a beautiful pond filled with orange and white koi.
- Collectors often pay significant sums for koi with rare scale patterns and vibrant, symmetrical markings.

## Examples

- The team found a new koi that might be an Earth-like planet.
- After analyzing the light curves from the telescope, the researchers identified a promising koi in the Cygnus constellation.
- While thousands of stars were flagged as a koi during the initial mission, many were later reclassified as false positives caused by eclipsing binary star systems rather than orbiting planets.

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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.