“Grexit” (Greece/Greek + exit) is a word created to define a possible Greek exit from the eurozone. The term was coined in February 2012 by Citigroup economists Willem Buiter and Ebrahim Rahbari, co-authors of the paper “Rising Risks of Greek Euro Area Exit.”
 
“Grexit” became increasing popular in 2012 as the possibility of a Greek exit of the eurzone increased; Willem Buiter alone has usually been credited for the term.
 
“Gerxit” (Germany/German + exit) and “Spexit” (Spain/Spanish + exit) both date from May 2012. “Brexit” (Great Britain/British + exit) dates from May 2012 and “Brixit” (Great Britain/British + exit) dates from June 2012.
     
 
Word Spy
Grexit
n. The exit of Greece from the eurozone. [Greece or Greek + exit.]
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Earliest Citation:
In this piece, we make two key points: First, we raise our estimate of the likelihood of Greek exit from the eurozone (or “Grexit”) to 50% over the next 18 months from earlier estimates of ours which put it at 25-30%.
—William Buiter and Ebrahim Rahbari, “Rising Risks of Greek Euro Area Exit,” Citigroup Global Markets, February 6, 2012
   
About.com: Greece Travel
Grexit
By deTraci Regula, About.com Guide
Definition: If you haven’t seen this word before, you’re not alone. It’s a newly-coined term created by Citigroup’s Willem Buiter. It combines “Greek” or “Greece” with the word “exit” and refers to the possibility of Greece leaving the Eurozone. The word has been picked up by media worldwide and it may well worm its way into the official lexicon. And it certainly has Greek roots beyond the obvious “Gr” - the word “exit” itself comes from the Greek “exodos”, meaning “going out”.
 
Wikipedia: Willem Buiter
Willem Hendrik Buiter (born September 26, 1949, in The Hague, Netherlands) is a Dutch-born American economist, also of British nationality, who is Professor of European Political Economy at the London School of Economics and Political Science. He has served as chief economist of the European Bank for Reconstruction and Development, external member of the Bank of England’s Monetary Policy Committee, and as an advisor and consultant for a number of national governments and private financial enterprises.
 
WillemBuiter.com
“Rising Risks of Greek Euro Area Exit”, with Ebrahim Rahbari, Citi Economics, Global Economics View, 6 February 2012.
 
Business Insider
CITI’S BUITER: There’s A 50% Chance Of A Greek Exit From The Eurozone And Here’s How It Would Happen
Simone Foxman|Feb. 7, 2012, 7:15 AM
Citigroup economists Willem Buiter and Ebrahim Rabhari revised their predictions of a Greek exit from the eurozone—or “Grexit”—in the next 18 months up to 50 percent from 25-30 percent in November.
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Still, Grexit is not Citigroup’s baseline scenario—Buiter and Rabhari expect that a Greek default will indeed provoke a credit event, and that future debt restructuring will have to happen, but that it will stay in the eurozone.
   
Business Insider
Greece is headed for another election, Eurozone exit is now the central case of consensus
Also Sprach Analyst|May 15, 2012, 10:52 AM
After Greece failed to form a coalition government after the latest election, Greece is headed for yet another election.  The immediate result is a steep dive of EURUSD.
 
With yet another election imminent in Greece after the failure to form a new government, the political chaos in Greece has substantially increased the probability of a Greek eurozone, or as Willem Buiter of Citi called it, a “Grexit”.   
 
International Business Times
Grexit and Bank Run Prospects Continue to Weigh on the Euro
By Fan Yang
May 15, 2012 7:35 PM GMT
Under the spotlight again, Greece is now at the brink of an exit from the European Monetary Union (EMU). Breakdown in coalition talk further puts pressure on the euro. German Finance Minister Wolfgang Schaeuble is calling the vote a “referendum on whether the country stays in the euro” as noted in Bloomberg.com. If the re-election puts an anti-bailout parilament leader in charge ie. Evangelos Venizelos of the socialist Pasok party, we can expect direction of a Greek Exit (Grexit).