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cas·tor¹

(kăstər)

1. An oily, brown, odorous substance obtained from glands in the groin of the beaver and used as a perfume fixative. Also called castoreum.

2. A hat made of beaver fur or an imitation.

3. A heavy wool fabric used especially for overcoats.

[Middle English, from Latin, beaver, from Greek kastōr.]

cas·tor²

(kăstər)

Variant of caster.

cast·er

(kăstər)

1. One that casts: a caster of nets.

2. also cas·tor (kăstər) A small wheel on a swivel, attached under a piece of furniture or other heavy object to make it easier to move.

3. also castor

a. A small bottle, pot, or shaker for holding a condiment.

b. A stand for a set of condiment containers.

Cas·tor

(kăstər)

1. Greek Mythology One of the Dioscuri.

2. A binary star in the constellation Gemini, approximately 46 light years from Earth and of roughly equal brightness with Pollux.

[Latin, from Greek Kastōr, twin of Pollux.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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