[Elamur Dictionary](https://md.dictionary.elamur.ai/free/en/) · [this page in HTML](https://dictionary.elamur.ai/free/en/english/castor/)

[dictionaries](https://md.dictionary.elamur.ai/free/en/) / [English](https://md.dictionary.elamur.ai/free/en/english/) / [C](https://md.dictionary.elamur.ai/free/en/english/c/) / castor

# castor

noun (a castor, castors; castor — uncountable in "castor oil"); name (Castor)

«castor» in the English dictionary: everyday — its meanings, how the lessons use it, and examples, each with its tree on Mova.

## Everyday

1. A small wheel fixed under a chair, bed, trolley or piece of furniture so it can be moved easily (also spelled "caster"). [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#m1)
2. In "castor oil": a thick, bad-tasting oil from the seeds of the castor oil plant, once given to children as a medicine. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#m2)
3. In "castor sugar" (UK, also "caster sugar"): very fine white sugar used in baking. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#m3)
4. (a name) Castor is a bright star in the Gemini constellation, named after one of the twins in Greek myths. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#m4)
5. Castor can also be the name of a twin hero from Greek myths, who was a famous horseman. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#m5)

### In the lessons

In everyday life office chairs and hospital beds roll on castors. In history and old stories castor oil was a nasty medicine children dreaded. In baking lessons caster or castor sugar dissolves quickly in cakes and meringues. In astronomy, Castor and Pollux are the twin stars of Gemini.

### Examples

- The office chair rolls on five castors. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#x1)
- One castor broke, so the trolley wobbles. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#x2)
- In old books, children were given a spoon of castor oil. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#x3)
- Use castor sugar to make meringues. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#x4)
- Castor and Pollux are the brightest stars in Gemini. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#x5)
- Castor oil comes from the seeds of the castor bean plant. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#x6)
- They were also famous for their physical accomplishments, Castor being the most expert charioteer of his day, and Pollux the first of pugilists. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/#x7)

### Note

Spelling: both castor and caster are used for the wheel and the sugar. Safety: the seeds of the castor oil plant are very poisonous to eat, though the oil itself is processed safely. The star Castor has a capital C.

## On Mova

- [Trees and pragmatics of «castor» in the school dictionary](https://mova.elamur.ai/free/en/corpora/dictionaries/school/C/castor/): every meaning and example parsed by Mova, with its dependency tree and frames.
- [«castor» in the school dictionary](https://mova.elamur.ai/free/en/dictionaries/school/w/castor.html) on Mova free.