b or B /ˈbi:/ nounplural b's or bs or B's or Bs
1 : the second letter of the English alphabet [count] ▪ There are two b's in the word “abbey.” [noncount] ▪ All of their children's names begin with b.2 : a musical note or key referred to by the letter B : the seventh tone of a C-major scale [count] ▪ play/sing a B [noncount] ▪ a song in the key of B3 [count] : a grade that is given to a student for doing good work
▪ got a B in math ▪ He's a B student. [=a student who gets B's for his schoolwork]4 [noncount] — used to refer to the second of two or more people, places, or things that are being considered ▪ We chose option B over option A.
▪ got a B in math ▪ He's a B student. [=a student who gets B's for his schoolwork]
from (point) A to (point) B — see 1a