B - Definition

n 1: aerobic rod-shaped spore-producing bacterium; often
occurring in chainlike formations; found primarily in soil
[syn: bacillus, B]
2: originally thought to be a single vitamin but now separated
into several B vitamins [syn: B-complex vitamin, B
complex, vitamin B complex, vitamin B, B vitamin, B]
3: a trivalent metalloid element; occurs both in a hard black
crystal and in the form of a yellow or brown powder [syn:
boron, B, atomic number 5]
4: a logarithmic unit of sound intensity equal to 10 decibels
[syn: Bel, B]
5: (physics) a unit of nuclear cross section; the effective
circular area that one particle presents to another as a
target for an encounter [syn: barn, b]
6: the 2nd letter of the Roman alphabet [syn: B, b]
7: the blood group whose red cells carry the B antigen [syn:
B, type B, group B]