US slang. : to make an offensive gesture at (someone) by pointing the middle finger upward while keeping the other fingers folded down angry drivers flipping each other the bird.

Is Flip the bird an idiom?

When you say 'Flip the Bird' you mean someone is making a rude, crude gesture by extending their middle finger.

Where did flipping the bird originate from?

Otherwise known as “giving the finger” or the “one-finger salute,” flipping the bird has its origins in ancient Greece, becoming the obscene hand gesture it's known for today.