B51 or B-51 may refer to:
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HLA-B51
HLA-B51 (B51) is an HLA- B serotype. The serotype identifies the more common HLA-B*51 gene products.
B51 is a split antigen of the broad antigen B5, and is a sister serotype of B52. There are many alleles within the B*51 allele group. B51 is ...
, an HLA-B serotype
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Bundesstraße 51
The Bundesstraße 51 (translates from German ''Federal road'', abbreviated as B 51) runs from Bremen in south-west direction though Lower Saxony, North Rhine-Westphalia, Rhineland-Palatinate and Saarland, and ends at the French border in the tow ...
, a road in western Germany
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Martin XB-51
The Martin XB-51 was an American trijet ground-attack aircraft. It was designed in 1945 and made its maiden flight in 1949. It was originally designed as a bomber for the United States Army Air Forces under specification V-8237-1 and was desig ...
, an American airplane
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Sicilian Defence, in the Encyclopaedia of Chess Openings
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B51 (New York City bus)
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