# castor
## English
### Pronunciation

* (Received Pronunciation) IPA: /ˈkɑːs.tə/
* Audio (Southern England):(file)
* (General American) IPA: /ˈkæs.tɚ/
* Rhymes: -ɑːstə(ɹ), -æstə(ɹ)
* Homophone: caster

### Etymology 1

From Middle French castor, from Old French castor (“beaver”), from Latin castor (“beaver”), from Ancient Greek κάστωρ (kástōr), from Doric Greek κάστον (káston, “wood”).

#### Noun

castor (countable and uncountable, plural castors)
* A hat made from the fur of the beaver.
** 1826, [Walter Scott], chapter V, in Woodstock; Or, The Cavalier. […], volume I, Edinburgh: […] [James Ballantyne and Co.] for Archibald Constable and Co.; London: Longman, Rees, Orme, Brown, and Green, →OCLC, page 135:I have been always noted for the jaunty manner in which I wear my castor— […]
* A heavy quality of broadcloth for overcoats.
* Castoreum (bitter exudate of mature beavers).
* Any of various nymphalid butterflies of the genus Ariadne, of Africa and Asia.

##### Synonyms

* (hat): beaver, castoreum (archaic)
* (cloth): beaver

##### Derived terms

* castorin

##### Related terms

* castorette
* castoreum

##### See also

* castor bean
* castor oil
* castor sac

### Etymology 2

Named from Greek mythology; see Castor and Pollux. The name pollux was given to another mineral with which it was always found.

#### Noun

castor (uncountable)
* (mineralogy) A variety of petalite found in Elba.

##### Synonyms

* castorite

### Etymology 3

Alternative spelling of caster, via cast +‎ -or (the Latinate varient of -er).

#### Noun

castor (plural castors)
* (especially UK) Alternative spelling of caster, especially in its senses
** A pivoting roller attached to the bottom of furniture to allow it to be moved.
** A container with a perforated cap for sprinkling its contents, especially salt, pepper, etc.
*** 1851 November 14, Herman Melville, “The Ramadan”, in Moby-Dick; or, The Whale, 1st American edition, New York, N.Y.: Harper & Brothers; London: Richard Bentley, →OCLC, page 92:Mrs. Hussey soon appeared, with a mustard-pot in one hand and a vinegar-cruet in the other, having just broken away from the occupation of attending to the castors, and scolding her little black boy meantime.

##### Derived terms

* castor sugar
* castored
* castoring

### References

“castor”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.

### Anagrams

* Castro, Cators, Croats, acrost, actors, co-star, costar, scroat, scrota, tarocs

## Asturian
### Noun

castor m (plural castores)
* beaver

## Catalan
### Etymology

Borrowed from Latin castŏrem.

### Pronunciation

* IPA: (Central, Balearic) [kəsˈto]
* IPA: (Valencia) [kasˈtoɾ]
* Audio (Valencia):(file)

### Noun

castor m (plural castors)
* beaver

### Further reading

* “castor” in Diccionari de la llengua catalana, segona edició, Institut d’Estudis Catalans.

## French
### Etymology

Inherited from Middle French castor, from Old French castor, borrowed from Latin castor, itself from Ancient Greek κάστωρ (kástōr). Though borrowed into French early on, the word remained a more learned term at first, while bièvre was the popular synonym.

### Pronunciation

* IPA: /kas.tɔʁ/
* Audio:(file)
* Audio (Paris):(file)
* Homophone: castors

### Noun

castor m (plural castors)
* beaver (aquatic mammal)
    Synonym: (archaic) bièvre

#### Derived terms

* castor commun
* castor d’Eurasie
* castor d’Europe

### Further reading

* “castor”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012.

### Anagrams

* scorât

## Galician
### Etymology

From Latin castor (“beaver”).

### Pronunciation

* IPA: /kasˈtoɾ/

### Noun

castor m (plural castores)
* beaver
    Synonym: befre

### Further reading

* “castor”, in Dicionario da Real Academia Galega (in Galician), A Coruña: Royal Galician Academy, 2012–2025

## Latin
### Etymology

From Ancient Greek κάστωρ (kástōr), from Doric Greek κάστον (káston, “wood”). See also Sanskrit कस्तूरी (kastūrī, “musk”).

### Pronunciation

* (Classical Latin) IPA: /ˈkas.tor/, [ˈkäs̠t̪ɔr]
* (modern Italianate Ecclesiastical) IPA: /ˈkas.tor/, [ˈkäst̪or]

### Noun

castor m (genitive castoris); third declension
* beaver

#### Declension

Third-declension noun.

#### Synonyms

* fiber, beber (Late Latin)

#### Derived terms

* castoreātus
* castoreum
* castorīnātus
* castorīnus

#### Related terms

* Castor

#### Descendants

* → Catalan: castor
* → Old French: castor
** Middle French: castor
*** French: castor
*** → English: castor
* → Friulian: castôr
* → Galician: castor
* → Italian: castoro
* → Portuguese: castor
* → Romanian: castor
* → Spanish: castor

### See also

* Castor

### References

* “castor”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
* “castor”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
* castor in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
* castor in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.
* “castor”, in Harry Thurston Peck, editor (1898), Harper's Dictionary of Classical Antiquities, New York: Harper & Brothers
* “castor”, in William Smith, editor (1848), A Dictionary of Greek and Roman Biography and Mythology, London: John Murray

### Anagrams

* Arctos

## Norman
### Etymology

Borrowed from French castor, from Latin castor (“beaver”).

### Noun

castor m (plural castors)
* (Jersey) beaver

## Portuguese
### Etymology

From Latin castōrem (“beaver”), from Ancient Greek κάστωρ (kástōr).

### Pronunciation

* (Brazil) IPA: /kasˈtoʁ/ [kasˈtoh]
* (Brazil) IPA: /kasˈtoʁ/ [kasˈtoh]
** (São Paulo) IPA: /kasˈtoɾ/
** (Rio de Janeiro) IPA: /kaʃˈtoʁ/ [kaʃˈtoχ]
** (Southern Brazil) IPA: /kasˈtoɻ/
* (Portugal) IPA: /kɐʃˈtoɾ/
* (Portugal) IPA: /kɐʃˈtoɾ/
** (Southern Portugal) IPA: /kɐʃˈto.ɾi/
* Hyphenation: cas‧tor

### Noun

castor m (plural castores)
* beaver
* fur of a beaver
* castor (a hat made from the fur of the beaver)

#### Derived terms

* castor-americano
* castor-de-kellogg
* castor-europeu
* castor-gigante
* castorenho

### Further reading

* “castor” in Dicionário Aberto based on Novo Diccionário da Língua Portuguesa de Cândido de Figueiredo, 1913
* “castor”, in Michaelis Dicionário Brasileiro da Língua Portuguesa (in Portuguese), São Paulo: Editora Melhoramentos, 2015–2025
* “castor”, in Dicionário Priberam da Língua Portuguesa (in Portuguese), Lisbon: Priberam, 2008–2025

## Romanian
### Etymology

Borrowed from French castor and its source, Latin castor, from Ancient Greek κάστωρ (kástōr).

### Noun

castor m (plural castori)
* beaver
    Synonyms: breb (“European beaver”); (less common) biber

#### Declension
### Further reading

* castor in DEX online—Dicționare ale limbii române (Dictionaries of the Romanian language)

## Spanish
### Etymology

From Latin castor (“beaver”).

### Pronunciation

* IPA: /kasˈtoɾ/ [kasˈt̪oɾ]
* Audio (Colombia):(file)
* Rhymes: -oɾ
* Syllabification: cas‧tor

### Noun

castor m (plural castores)
* beaver

### Further reading

* “castor”, in Diccionario de la lengua española [Dictionary of the Spanish Language] (in Spanish), online version 23.8, Royal Spanish Academy [Spanish: Real Academia Española], 2024 December 10