From AMS Glossary
A wind, named after the Maloja Pass between the Engadine and Bergall, Switzerland, that blows down the valley of the Upper Engadine by day and either up or down by night.
This deviation from the usual nature of mountain and valley winds is attributed to the fact that the stronger daytime valley wind from the south overtops the ridge and continues down the Engadine.
Defant, F. 1951. Compendium of Meteorology. p. 664.