Gulf stream and Ocean current

Gulf stream noun - A warm ocean current that flows from the Gulf of Mexico northward through the Atlantic Ocean.

Ocean current and gulf stream are semantically related. In some cases you can use "Ocean current" instead a noun phrase "Gulf stream".

Ocean current noun - The steady flow of surface ocean water in a prevailing direction.

Gulf stream and ocean current are semantically related. Sometimes you can replace phrase "Gulf stream" with "Ocean current", this phrases are similar.