Definition of "multiday"

Entering a whole new realm of high seasonally averaged temperatures, not just multiday heat waves, will surely challenge the global population's ability to produce adequate food in the future or even to cope physically with chronic heat stress, unless major adaptations are made.

2009 January 9, David. S. Battisti, Rosamond L. Naylor, “Historical Warnings of Future Food Insecurity with Unprecedented Seasonal Heat”, in Science‎, volume 323, number 5911