D66 may refer to:
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Delta Junction Airport, a public airport in Alaska with FAA code D66
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d66 (die), a dice roll used in some role-playing games and old wargames
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D66 road (Croatia), a state road in Croatia
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Democrats 66
Democrats 66 (; abbreviated D66, ) is a Social liberalism, social liberal List of political parties in the Netherlands, political party in the Netherlands, which positions itself in the Centrism, centre of the Left–right political spectrum, p ...
, commonly known as D66, a political party in the Netherlands
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HMS ''Emerald'' (D66), an ''Emerald''-class light cruiser
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D66 strain of ''Chlamydomonas reinhardtii''
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Queen's Gambit Declined
The Queen's Gambit Declined (or QGD) is a chess opening in which Black declines a pawn offered by White in the Queen's Gambit:
:1. d4 d5
:2. c4 e6
This is known as the ''Orthodox Line'' of the Queen's Gambit Declined. When the "Queen's Gambi ...
, ''Encyclopedia of Chess Openings'' code
{{Letter-number combination disambiguation