The idiom "bad apple" refers to a person who is a bad influence on others, or someone who is dishonest or untrustworthy. This phrase is often used to describe someone who is part of a group or organization, but whose behavior is negative and can affect the entire group.
For example, if a group of friends are all studying for an exam, but one friend is constantly distracting the others and not taking the studying seriously, that person could be referred to as a "bad apple" because their behavior is negatively impacting the group's ability to succeed.
Similarly, if an employee in a company is engaging in unethical behavior or breaking company rules, they could be referred to as a "bad apple" because their actions could harm the reputation and success of the entire company.
Overall, the idiom "bad apple" is used to describe someone who is a negative influence on a group or organization, and whose behavior could potentially harm the success or reputation of that group or organization.
• The new employee turned out to be a bad apple, stealing office supplies.
• It's difficult to weed out the bad apple when they're hiding among the good ones.
• The company had to fire the bad apple to maintain its reputation.
• I'm sorry, but I can't trust him; he's a bad apple.
• My brother is a bad apple; he never cleans his room.
• Despite our best efforts, there's always a bad apple in every group.