| Idiom | Meaning | Example | 
| butter up | 
be nice to, suck up to
 | 
Butter him up before you ask to borrow his car.
 | 
| butter wouldn't melt in his mouth | 
he is very calm and clear, he has an air of innocence, 
cool, smooth talker
 | 
When he's talking to voters, butter wouldn't melt in his mouth.
 | 
| button your lip | 
do not tell anyone, on the QT
 | 
Button your lip about the speeding ticket. Don't tell Dad.
 | 
| buttonhole you | 
stop you and talk to you, corner you and bore you
 | 
At the meeting, Al buttonholed me and asked me to vote Reform.
 | 
| buy a round | 
buy a drink for everyone at the table, this one is on me
 | 
When Gina was born, I bought a round for the team. Every player had a drink to honor our baby.
 | 
| buy into | 
believe and support, agree to support, come onside
 | 
He will buy into our plan if the money goes to needy children.
 | 
| buy out | 
buy a business and all the inventory
 | 
We knew his business was in debt,  so we offered to buy him out.
 | 
| buy that | 
believe that, eat that
 | 
He says he went to see his friends at the park. I can buy that.
 | 
| buy the farm | 
die, kick the bucket, pass away
 | 
"Where's Henry?" "Oh, he bought the farm years ago - died of cancer, eh."
 | 
| buy time | 
request time to plan, ask for extra time
 | 
If we can just buy a little time, maybe the price will go down.
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