An oceangoing ship is built for the real ocean — the wide salt water between countries — not for a river, a lake, or a short hop along the coast. These ships are bigger and stronger, with hulls and engines that can take weeks of waves, wind, and salt. You will meet the word most often in front of ship, vessel, tanker, or yacht: an oceangoing tanker, an oceangoing yacht. People also write ocean-going, with a hyphen; it means the same. The word feels a bit technical, the kind of thing you read in news about trade or long travel, not in everyday chat. Though actually, some speakers stretch it. They borrow the “big and built for the real sea” feeling and use oceangoing for a huge, full-strength version of something else, like an oceangoing row. That looser use is informal, and it is not the main meaning.

遠洋的（船）