trade wind

 
Pronunciation: /ˈtreɪdwɪnd/

noun

  • a wind blowing steadily towards the equator from the north-east in the northern hemisphere or the south-east in the southern hemisphere, especially at sea. Two belts of trade winds encircle the earth, blowing from the tropical high-pressure belts to the low-pressure zone at the equator.

Origin:

mid 17th century: from the phrase blow trade 'blow steadily in the same direction'. Because of the importance of these winds to navigation, 18th-century etymologists were led erroneously to connect the word trade with ‘commerce’