English Wikipedia has a category on:
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Commons:Category
Commons:Category
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Newest and oldest pages 
Newest pages ordered by last category link update:
  1. sea change
  2. Timor Sea
  3. English Channel
  4. Yellow Sea
  5. Gulf of Tonkin
  6. Bering Sea
  7. East China Sea
  8. seasteading
  9. Sea of Okhotsk
  10. Sea of Marmara
Oldest pages ordered by last edit:
  1. Ionian Sea
  2. Bay of Bengal
  3. English Channel
  4. Ceram Sea
  5. Java Sea
  6. Mazandaran Sea
  7. Seto Inland Sea
  8. Sargasso Sea
  9. Norwegian Sea
  10. Barents Sea

English names of seas.

NOTE: This is a name category. It should contain names of specific seas, not merely terms related to seas, and should also not contain general terms for types of seas.