{not} [know] beans about {sth}
1
to have no information regarding a particular subject
The origin of the idiom "not know beans about something" can be traced back to early 20th-century American slang. "Beans" in this context is used metaphorically to represent knowledge or expertise, with "not knowing beans" indicating a lack of understanding or familiarity with a particular subject or topic. This idiom is typically used to convey a person's ignorance or incompetence in a specific area.
- I don't know beans about car engines, so I rely on the mechanic to explain what's wrong.
- He claims to be a tech expert, but he doesn't know beans about troubleshooting computer issues.
- She doesn't know beans about gardening, so she's taking a gardening class to learn.
- You can't trust his financial advice; he doesn't know beans about investing.