Need advice on what is the the difference between panic disorder and a nervous breakdown?

Dx vs layman's term: Nervous breakdown is not a medical term, nor does it describe a specific mental illness. But that doesn't mean it's a normal response to stress. A nervous breakdown may indicate an underlying mental health problem that needs attention, such as depression or anxiety. Each person's may be different. Panic disorder is a dsm dx. Talk with a therapist to understand and help with what is wrong.