American Heritage Dictionary
(2)
Century Dictionary
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GNU Webster's 1913
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WordNet
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Elsewhere on the web
That came after newly-installed Arima Race Club (ARC) chief executive officer Ken Ogeer and ARC president Kama Maharaj relented to the jockeys 'ultimatum, after consulting with the sponsors and a legal official.— TrinidadExpress Today's News
Sources close to De Beers claim the ultimatum was a bluff by senior executives in London, in order to halve the $100 million payment which De Beers must pay LUKoil if the agreement is finalized with the Kremlin.— Asia Times Online
That's not an ultimatum -- that's a nod and a wink.— WSJ.com: What's News US

American Heritage Dictionary (1)
Century Dictionary (1)
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