Buy off
Definition 1 of 1
Pro Tip 1/3Negative connotation
The phrase 'buy off' implies a dishonest or unethical action. 
They tried to buy off the witnesses to ensure silence.
Pro Tip 2/3Colloquial usage
'Buy off' is informal and usually not used in formal or professional situations. 
He wanted to buy off the competition, not beat them fairly.
Pro Tip 3/3Cultural perception
In many cultures, the act of 'buying off' is considered corrupt and is illegal. 
The company got fined for trying to buy off local officials.