B- may refer to:
*B-, a
blood type
A blood type (also known as a blood group) is a classification of blood, based on the presence and absence of antibodies and inherited antigenic substances on the surface of red blood cells (RBCs). These antigens may be proteins, carbohydrate ...
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B- (grade), an academic grade
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B − L, ('B minus L'), the difference between the baryon number (B) and the lepton number (L)
{{Disambiguation