I'm not sure that I understand your grammatically incorrect question.
What IS the major ocean in the world?
What ARE the major oceanS of the world?
As to the major ocean, being singular... it depends on:
Just because it is potentially useful for one thing doesn't mean that the other oceans aren't useful for something else.
As to the major oceans, being plural, Pacific, Atlantic, Indian, Southern, and Arctic.
Their are 5 main oceans:Pacific OceanAtlantic OceanIndian OceanArctic OceanThe southern Ocean
The pacific ocean
Antarctica is located south of the four major oceans of the world: the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, and the Southern Ocean.
PAcific Ocean the largest ocean in the world.
Indian Ocean ect
Antarctica
the temperature of the water in the upper layers of the ocean
The Pacific is by far the largest of the oceans.
The Atlantic ocean is more major, I think because it is one of the 5 oceans in the world. Seas aren't as important.
There are five mahasagars, or major oceans, in the world: the Pacific Ocean, Atlantic Ocean, Indian Ocean, Southern (Antarctic) Ocean, and Arctic Ocean. Each ocean plays a significant role in regulating the Earth's climate and supporting marine ecosystems.
Europe and the Pacific Ocean.
When viewing the world from its side, the Pacific Ocean is the major body of water that separates the two continents. When viewing the world from the North Pole, the Arctic Ocean separates the two continents.