As nouns,
El Nino southern oscillation is a hyponym of
El Nino; that is,
El Nino southern oscillation is a
word with a more specific, narrower meaning than
El Nino:
- El Nino: (oceanography) a warm ocean current that flows along the equator from the date line and south off the coast of Ecuador at Christmas time
- El Nino southern oscillation: a more intense El Nino that occurs every few years when the welling up of cold nutrient-rich water does not occur; kills plankton and fish and affects weather patterns