B

(noun) aerobic rod-shaped spore-producing bacterium; often occurring in chainlike formations; found primarily in soil. Synonyms: bacillus.

(noun) originally thought to be a single vitamin but now separated into several B vitamins. Synonyms: B-complex vitamin, B complex, vitamin B complex, vitamin B, B vitamin.

(noun) a trivalent metalloid element; occurs both in a hard black crystal and in the form of a yellow or brown powder. Synonyms: boron, atomic number 5.

(noun) a logarithmic unit of sound intensity equal to 10 decibels. Synonyms: Bel.

(noun) (physics) a unit of nuclear cross section; the effective circular area that one particle presents to another as a target for an encounter. Synonyms: barn, b.

(noun) the 2nd letter of the Roman alphabet. Synonyms: b.

(noun) the blood group whose red cells carry the B antigen. Synonyms: type B, group B.