The term 'Deep-Sea Oxygen Supplier' refers to an organism that provides oxygen to the deep sea. This organism is commonly referred to as a GILL, which is a four letter word. Gills are organs that allow aquatic animals to extract oxygen from the water around them. They are found in many species of fish, amphibians, and some invertebrates. Gills are essential for these organisms to survive in the deep sea, where oxygen levels are much lower than in shallow waters.