| Idiom | Meaning | Example |
| blue moon |
rare event, unusual happening, that'll be the frosty Friday
|
If he ever says thank you there'll be a blue moon in the sky!
|
| blue sky |
great opportunity, easy life, smooth sailing
|
We made T-shirts, and people loved them and bought them.
From then on, it was blue sky!
|
| blurt out |
say without thinking, reply quickly
|
"I did it!" the boy blurted out, and he began to cry.
|
| boarding (hockey) |
checking into the boards, chairman of the boards
|
Boarding causes serious injuries to hockey players.
|
| Bob's your uncle |
no problem as "Bob," a powerful friend or relative, will do it or have it done
|
When I asked her to give your application to the president, she said, "Bob's your uncle!"
|
| bodacious |
bold, daring, defying the rules, like a daredevil
|
He's bodacious alright. He rode his skateboard right through traffic!
|
| body language |
body movements that show feelings
|
Your body language tells me that you're tense. Please relax.
|
| boggle your mind |
confuse you, make your head spin
|
These numbers boggle my mind. I don't understand them.
|
| bogof |
buy one get one free, marketing method, loss leader
|
If you shop for bogof items you get two for the price of one!
|
| boiling mad |
very angry, very upset, hopping mad
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By the time the car started, Emil was boiling mad.
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