from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun Greek Mythology One of the Dioscuri.
  • noun A double star in the constellation Gemini, approximately 46 light years from Earth and of roughly equal brightness with Pollux.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • proper noun A taxonomic genus within the family Castoridae — the beavers.
  • proper noun Greek mythology One of the Dioscuri
  • proper noun astronomy A double star in the constellation Gemini; alpha (α) Geminorum.


from The American Heritage® Dictionary of the English Language, 4th Edition

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

from Wiktionary, Creative Commons Attribution/Share-Alike License

1398 Old French castor, from Latin castor ("beaver"), from Ancient Greek Κάστωρ (Kastor).


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  • Sad to say, Florida's Catty Castor is part of this bullying group!

    Obama invites senators from both parties to discuss vacancy 2010

  • In addition, in-state efforts faltered as Colorado was only able to protect its borders for two prospects -- kicker Justin Castor and tight end Kyle Slavin.

    Colorado - Team Notes 2010

  • Castor is the more moderate of the two - Deutsch is running ads showing him being endorsed by Michael Moore - and while the campaign hasn't gotten as mean as the Republican race, it's not without its fireworks; Deutsch accused Castor of coddling terrorists when she was running USF because she didn't immediately fire a professor who expressed sympathy for the Palestinians.

    August 2004 2004

  • Here in Florida, Betty Castor is currently ahead and doing better upstate, such as in the Orlando area, than expected.

    November 2004 2004

  • I remember having seen Sophie Arnould twice at the opera, in "Castor and Pollux."

    Memoirs of Madame Vigée Lebrun 1903

  • The one he called Castor and the other Pollux, hoping they would live in such friendship together as did the two illustrious heroes, after whom they were named.

    Ami des enfants. English John Bewick 1769

  • At the same time Castor is brought onto a case about a man who’s been brutally raped and murdered.

    “Dead Men’s Boots” by Mike Carey (Grand Central Publishing, 2009) « The BookBanter Blog 2010

  • The Devil You Know includes story and character elements from his comic book writing, but also has its own individual feel about it; Felix Castor is a similar character to John Constantine, but this is also Carey style’s and one big reason why people enjoy his work.

    “The Devil You Know” by Mike Carey (Grand Central, 2007) « The BookBanter Blog 2010

  • Nor is there much fun, in the real-world sense of the term, except for a gleefully campy turn by Michael Sheen as a program called Castor — basically a nightclub owner — who warns Sam that he is about to cross the Sea of Simulation and it's "going to be quite a ride."

    Computer Epic 'TRON' Lacks Heart Drive Joe Morgenstern 2010

  • Howsoever it cometh to pass, men which all their lifetime had occupied the sea never saw more outrageous seas, we had also upon our mainyard an apparition of a little fire by night, which seamen do call Castor and Pollux.

    Sir Humphrey Gilbert's Voyage to Newfoundland Edward Hayes


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