Standard Lemma guide

castor

name · noun · 18 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.

  • Received-Pronunciation: /ˈkɑːs.tə/
  • General-American: /ˈkæs.tɚ/
  • US: Recorded audio is listed in the source snapshot.
  • Southern-England: Recorded audio is listed in the source snapshot.
  • rhymes with -ɑːstə(ɹ)
  • rhymes with -æstə(ɹ)
  • homophone: caster
  • CMU ARPABET: K AE1 S T ER0 Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.

1

name

Meaning 1

One of the Dioscuri

Definition source: English Wiktionary via Wiktextract

Usage: Greek

Topics: human-sciences, mysticism, mythology, philosophy, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

name

Meaning 2

A double star in the constellation Gemini; alpha (α) Geminorum.

Definition source: English Wiktionary via Wiktextract

Topics: astronomy, natural-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

name

Meaning 3

A village and civil parish in city of Peterborough district, Cambridgeshire, England (OS grid ref TL1298).

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

4

name

Meaning 4

A town in the County of Paintearth, Alberta, Canada. From French castor (“beaver”).

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

5

name

Meaning 5

A village in Bienville Parish, Louisiana, United States. From French castor (“beaver”).

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

6

name

Meaning 6

A surname.

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

7

noun

Meaning 7

A hat made from the fur of the beaver.

Definition source: English Wiktionary via Wiktextract

Usage: countable, uncountable

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

8

noun

Meaning 8

A heavy quality of broadcloth for overcoats.

Definition source: English Wiktionary via Wiktextract

Usage: countable, uncountable

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

9

noun

Meaning 9

Castoreum (bitter exudate of mature beavers).

Definition source: English Wiktionary via Wiktextract

Usage: countable, uncountable

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

10

noun

Meaning 10

Any of various nymphalid butterflies of the genus Ariadne, of Africa and Asia.

Definition source: English Wiktionary via Wiktextract

Usage: countable, uncountable

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

11

noun

Meaning 11

A variety of petalite found in Elba.

Definition source: English Wiktionary via Wiktextract

Usage: uncountable

Topics: chemistry, geography, geology, mineralogy, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

12

noun

Meaning 12

Alternative spelling of caster, especially in its senses

A pivoting roller attached to the bottom of furniture to allow it to be moved.

Definition source: English Wiktionary via Wiktextract

Usage: UK, especially

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

13

noun

Meaning 13

Alternative spelling of caster, especially in its senses

A container with a perforated cap for sprinkling its contents, especially salt, pepper, etc.

Definition source: English Wiktionary via Wiktextract

Usage: UK, especially

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

14

noun

Meaning 14

type genus of the Castoridae: beavers

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: genus Castor

Antonyms: none provided

Broader terms: mammal genus

15

noun

Meaning 15

a hat made with the fur of a beaver (or similar material)

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: beaver

Antonyms: none provided

Broader terms: fur hat

16

noun

Meaning 16

a pivoting roller attached to the bottom of furniture or trucks or portable machines to make them movable

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: caster

Antonyms: none provided

Broader terms: roller

17

noun

Meaning 17

a shaker with a perforated top for sprinkling powdered sugar

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: caster

Antonyms: none provided

Broader terms: shaker

18

noun

Meaning 18

a multiple star with 6 components; second brightest in Gemini; close to Pollux

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: Alpha Geminorum

Antonyms: none provided

Broader terms: multiple star

History

Etymology

From Ancient Greek Κάστωρ (Kástōr), from Ancient Greek κάστωρ (kástōr, “beaver”).

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

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

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

Across languages

Translations

25 source translations are retained for this English entry.

  • Danish: Castor — Dioscuri
  • French: Castor — Dioscuri
  • Greek: Κάστωρ (Kástor) — Dioscuri
  • Greenlandic: Kastori — Dioscuri
  • Inuktitut: ᑲᔅᑐᕐ (kastor) — Dioscuri
  • Irish: Castór — Dioscuri
  • Polish: Kastor — Dioscuri
  • Russian: Ка́стор (Kástor) — Dioscuri
  • Chinese Cantonese: 北河二 (bak1 ho4 ji6) — Star
  • Chinese Mandarin: 北河二 (Běihé'èr) — Star
  • Dutch: Castor — Star
  • French: Castor — Star
  • Greek: Κάστωρ (Kástor) — Star
  • Māori: Whakaahu rangi — Star
  • Māori: Whakaahu — Star
  • Polish: Kastor — Star
  • Russian: Ка́стор (Kástor) — Star
  • Scottish Gaelic: Gaolag na Caiginn — Star
  • Bulgarian: бобро́ва ша́пка (bobróva šápka) — hat
  • Czech: bobrovka — hat
  • Finnish: majavahattu — hat
  • Italian: castoro — hat
  • Polish: strój bobrowy — hat
  • Polish: kastoreum — hat
  • Russian: бобро́вая ша́пка (bobróvaja šápka) — hat
Real reading context

castor in complete knowledge articles