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

  • n. A coin containing a minting error.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A coin that is defective, having been incorrectly minted, often prized by collectors.


f(reaks), i(rregulars), d(efects), o(ddities).
(American Heritage® Dictionary of the English Language, Fourth Edition)
An acronym made up of the words freaks, irregulars, defects and oddities, from 1960's. (Wiktionary)


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  • Pronounced "fido" for the acronym FDO, it's used in NASA control rooms as a shortened version of Flight Dynamics Officer.

    July 25, 2009

  • Jennarenn, would you happen to be cracking wise at my giant heap of Wordie lists? ;-)

    October 10, 2007

  • THE list? That really narrows it down. ;)

    October 10, 2007

  • Wow! Never knew this one. Definitely goes on the list. :-)

    October 9, 2007

  • a coin with a minting error (freaks, irregulars, defects, oddities)

    October 9, 2007