The Greek word derives from the Greek word έτος (étos), meaning year, connotating their yearly fluctuation in frequency of appearance. Indeed, these winds have been described since ancient times and the word etesian (Greek: ετησίες) means annual. The Turkish form is probably a loan from Italian mal tempo 'bad weather'. Though it is sometimes called a monsoon wind, the meltemi is dry and does not correspond to an opposite wind in the winter. However, the etesians are distantly correlated with the summer monsoons of the Indian subcontinent, as it is a trough of low pressure into the Eastern Mediterranean region that enforces, if not causes, the etesians to blow in summer. A Mediterranean climate is sometimes called an etesian climate.
Etesians are due chiefly to the deep continental depression centered over southwest Asia and blow from a direction which may be anywhere between north-east and north-west depending on local topography; meltemi weather is ordinarily fine and clear, the northerly winds tempering the fierce summer heat of the region.
In the Northern Aegean sea, the etesians blow as winds of northeasterly to northerly direction. Moving south, in the central Aegean, they blow as winds of northerly direction, while, in the southern Aegean, the Cretan and the Carpathian sea, they blow as northwesterlies. The same winds blow in Cyprus as westerlies to southwesterlies, being more humid.
Historically, Philip II of Macedon timed his military operations so that powerful southern fleets could not reach him: their ships could not sail north while the Etesian winds were blowing.