Not know somebody from Adam

Pro Tip 1/3

The phrase is not about Adam; it's a way of saying you don't recognize someone.

Even though we worked in the same office, I wouldn’t know her from Adam.

Pro Tip 2/3

Use the phrase to emphasize that someone is as unfamiliar to you as it's possible to be.

The man in the photo could be anyone – I don’t know him from Adam.

Pro Tip 3/3

It often shows surprise that others expect you to recognize the person.

You know Mike from accounting? I don’t know him from Adam!