• Webster's Revised Unabridged Dictionary
    • a Etesian Periodical; annual; -- applied to winds which annually blow from the north over the Mediterranean, esp. the eastern part, for an irregular period during July and August.
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Century Dictionary and Cyclopedia
    • etesian Recurring every year; occurring at stated times of the year; periodical. The term was especially applied by Greek and Roman writers to the winds which blow from the north during the summer months, with great regularity and accompanied by a clear sky, over the Mediterranean, especially in its eastern portion. The etesian wind is the trade-wind abnormally prolonged toward the north by the peculiar climatic influences of the Sahara.
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Chambers's Twentieth Century Dictionary
    • adj Etesian e-tē′zhan periodical: blowing at stated seasons, as certain winds.
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Webster's Revised Unabridged Dictionary
L. etesiae, pl., periodic winds, Gr. , fr. year: cf. F. étésien,
Chambers's Twentieth Century Dictionary
L. etesius—Gr. etēsios, annual—etos, a year.


In literature:

And at dawn the Etesian winds blew strongly, which by the command of Zeus blow over every land equally.
"The Argonautica" by Apollonius Rhodius
Etesian Winds, ii 98; iv 81 n. 449.
"Tacitus: The Histories, Volumes I and II" by Caius Cornelius Tacitus
Those which blow constantly at certain seasons of the year, as monsoon, trade, and etesian winds.
"The Sailor's Word-Book" by William Henry Smyth
It is this "Etesian" wind which enables sailing boats constantly to ascend the Nile, against its strong and rapid current.
"Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 1" by Various