Answer: bneg

AnswerCrossword Clue
BNEG2% of the world's human blood: Abbr.
BNEGBlood type, for short
BNEGBlood type, briefly
BNEGUncommon blood type, briefly
BNEGRare blood type, for short
BNEGUncommon blood type, for short
BNEGBlood type: Abbr.
BNEGRare blood type, informally