Why sea is called sea and not an ocean?

Question

What makes sea a sea, and ocean an ocean? How we differentiate them?

In: 4

Answer 1

Seas are smaller than oceans. We only have 5 oceans, Pacific, Atlantic, and Indian, Artic, and Southern, but we have dozens of seas. If you want a rule of thumb then an Ocean has to cover at least a tenth of the world’s surface but honestly there’s no formal division, just regions defined as seas.