WordWeb Online

1. The property of being of, or pertaining to, a large geographic region.
   "In particular, the authors examine the link between the seasonality and regionality of the climate trends over the United States and the leading patterns of sea surface temperature (SST) variability, including a global warming (GW) pattern and a Pacific decadal variability (PDV) pattern."
    
2. The property of being of, or pertaining to, a specific region or district.
   "The party's regionality prevented it from winning a national election."

Derived forms: regionalities

Type of: arrangement, organisation [Brit], organization, particularity, specialness, system