1. not able to be relied on as honest or truthful

Examples

• The witness was considered untrustworthy due to his history of lying.
• She found the used car salesman to be untrustworthy and decided to shop elsewhere.
• His untrustworthy behavior cost him many friendships over the years.
• The company’s untrustworthy practices led to a major scandal.
• Parents warned their children about talking to untrustworthy strangers.
• The politician’s untrustworthy reputation made voters skeptical of his promises.