1
: one that casts
especially : a machine that casts type
2
or castor
a
: a usually silver table vessel with a perforated top for sprinkling a seasoning (such as sugar or spice)
b
: a usually revolving metal stand bearing condiment containers (such as cruets, mustard pot, and often shakers) for table use : a cruet stand
3
: any of a set of wheels or rotating balls mounted in a swivel frame and used for the support and movement of furniture, trucks, and portable equipment
4
: the slight usually backward tilt from vertical of the axis of the steering mechanism of an automobile for giving directional stability to the front wheels
1
2
3
: a beaver hat

castor

3 of 5
cas·​tor

variant spelling of caster

1
: one of the Dioscuri
2
: the more northern of the two bright stars in Gemini

castorite

5 of 5

noun

cas·​tor·​ite
ˈkastəˌrīt
-ˈaa-
-ˈai-
-ˈȧ-
plural -s
: a mineral consisting of a variety of petalite occurring in transparent crystal

Examples of caster in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
Highlights include the three spacious burners, swivel casters, electric push-button ignition and the capability to add on several cooking accessories. Bestreviews, Mercury News, 3 July 2026 Though technically more of an engineering achievement, casters have prevented untold back injuries that might have otherwise occurred from actually lifting furniture. Scott Lafee, San Diego Union-Tribune, 30 June 2026
Noun
For fine hair argan oil is ideal, while thick hair and curly and coily hair work better with heavier oils like castor or coconut oil. Ariana Yaptangco, Glamour, 5 July 2026 The formula also packs in microbiome-friendly ferments like Lactobacillus, Lactococcus, Bifida, and Saccharomyces extracts, alongside a nourishing blend of rosemary, peppermint, argan, castor, moringa, rosehip, jojoba, and soybean oils to support both scalp health and softer, silkier strands. Christa Joanna Lee, Allure, 27 May 2026
Noun
Packed with skin-loving ingredients like mango butter, green tea extract, and castor seed oil, this cream bronzer keeps your skin hydrated all day long without emphasizing texture or sinking into fine lines. Allure, 14 Aug. 2025 Meanwhile, castor seed oil, rambutan extract, and a blend of peptides help to nourish your lashes while coating them with high-impact color. Conçetta Ciarlo, Vogue, 11 Aug. 2025 See All Example Sentences for caster

Word History

Etymology

Noun (2)

Middle English, from Latin, from Greek kastōr, from Kastōr Castor

Noun (3)

Latin, from Greek Kastōr

Noun

castorite from German kastor (from Kastor mythological personage, from Latin Castor) + English -ite; castor from German kastor; from its appearance with pollucite (previously called pollux)

First Known Use

Noun (1)

14th century, in the meaning defined at sense 1

Noun (2)

14th century, in the meaning defined at sense 1

Noun (3)

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of caster was in the 14th century

Cite this Entry

“Caster.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/caster. Accessed 10 Jul. 2026.

Kids Definition

1
: one that casts
2
or castor : a small container (as for salt) with a top having small holes
3
: a small wheel that turns freely and is used for the support and movement of furniture

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