b

noun

ˈbē 

variants often B

plural b's or bs ˈbēz 

often attributive

1

a

: the 2nd letter of the English alphabet

names that begin with b

b

: a graphic representation of this letter

in the shape of a b

c

: the speech sound that the written letter b represents : a speech counterpart of orthographic b

2

: the seventh tone of a C-major scale (see scale entry 5 sense 1)

in the key of b

3

: a graphic device for reproducing the letter b

the b on the laptop's keyboard

4

: one designated b especially as the second in order or class

I chose option b.

5

a

: a grade rating a student's work as good but short of excellent

b

: one graded or rated with a B

a b student

6

: something shaped like the letter B

7

B : the one of the four ABO blood groups characterized by the presence of antigens designated by the letter B and by the presence of antibodies against the antigens present in the A blood group

Did you know?

Words Starting With B

Browse 22,618 words and phrases that start with the letter B, from baa to byzen.

Examples of b in a Sentence

There are two b's in the word “abbey.”

All of their children's names begin with b.

a song in the key of B

got a B in math

Recent Examples on the Web

The last time a He-Man and Skeletor movie was made was in 1987 and by then B-movie studio Cannon. —Anthony D'alessandro, Deadline, 3 June 2026

Reporter Ella Gonzales found brisket, sausage and a side for under $25 at Woody Creek Bar-B-Q near Ridgmar Mall. —Fort Worth Star-Telegram, 2 June 2026

Customers can also experience food fusions through a limited-time KC BBQ pizza collaboration with Joe’s Kansas City Bar-B-Que or an al pastor pizza — both through Father’s Day, or until supplies last at each location. —Sophie Lindberg, Kansas City Star, 2 June 2026

As anyone who wears an A- and B-cup knows, many styles are designed with large busts in mind. —Malia Griggs, Glamour, 1 June 2026

Word History

First Known Use

before the 12th century, in the meaning defined at sense 1a

Phrases Containing b

• b and w
• b-ball
• b-boy
• b-boying
• b-girl

Kids Definition

b

noun

ˈbē

often capitalized

1

: the second letter of the English alphabet

2

: a musical note referred to by the letter B : the seventh tone of a C-major scale

3

: a grade rating a student's work as good

Medical Definition

b

1 of 3 abbreviation

1

bacillus

2

barometric

3

bath

4

Baumé scale

5

behavior

6

bel

7

bicuspid

8

born

9

brother

B

2 of 3 noun

ˈbē 

: the one of the four ABO blood groups characterized by the presence of antigens designated by the letter B and by the presence of antibodies against the antigens present in the A blood group

B

3 of 3 symbol

boron