v.1. To contact, or attempt to contact, someone who has called previously, especially by telephone: When I got home from work, I called back my mother, who had left a message on my answering machine. I left a message asking the manager to call me back as soon as possible. I'll call back tonight when your parents are home.
2. To summon someone back to a previous situation or location: Just as I started walking away, the teacher called me back. The workers who were laid off are hoping that management will call them back as soon as the economy improves.
3. To recall something defective for repair: The company has called back all models of this car built in 2002. After discovering that the toy was unsafe for small children, the company was forced to call it back.