An Etymological Dictionary of Astronomy and Astrophysics

A seasonal change in wind direction bringing dry air or heavy rain in India and nearby lands.

Etymology (EN): Monsoon, from Du. monssoen, from Port. monçao, from Ar. mausim “season.” It was first applied to the winds over the Arabian Sea, which blow for six months from northeast and for six months from southwest, but it has been extended to similar winds in other parts of the world.

Etymology (PE): Bâd, → “wind;” mowsem, related to mowsem, from Ar. mausim, as above.