World Ocean part of hydrosphere
Geography
The entire ocean, containing 97% of Earth's water, spans 70.8% of Earth's surface, making it Earth's global ocean or world ocean. This makes Earth, along with its vibrant hydrosphere a "water world" or "ocean world", particularly in Earth's early history when the ocean is thought to have possibly covered Earth completely. The ocean is shaped irregularly, dominating Earth's surface unevenly, allowing the discernment of Earth's surface into a water and land hemisphere, as well as the division of the ocean into particular oceans.
a component of a constituent of an element of a fragment of a portion of