south wind vs air current

south wind and air current both are nouns.

Word	Noun	Adjective	Verb	Adverb
south wind	Yes	No	No	No
air current	Yes	No	No	No

As nouns, air current is a hypernym of south wind; that is, air current is a word with a broader meaning than south wind:

south wind: a wind from the south
air current: air moving (sometimes with considerable force) from an area of high pressure to an area of low pressure

Other hypernyms of south wind include current of air, wind.

south wind (noun)	air current (noun)
a wind from the south	air moving (sometimes with considerable force) from an area of high pressure to an area of low pressure