ring (or call or phone) someone back means return a phone call (e.g. I’ll ring back later.)
ring out means make a sudden loud sound (e.g. When a sound rings out, it is loud and clear.)
ring (or call or phone) someone back means return a phone call (e.g. I’ll ring back later.)
ring out means make a sudden loud sound (e.g. When a sound rings out, it is loud and clear.)