əˈridəd.ē, aˈ-, eˈ-, -ətē, -i noun
( -es )
Etymology: Latin ariditas, from aridus + -itas -ity
1. : the quality or state of being arid : dryness
the aridity of desert sands
2. : unavailability of water present in a habitat to organisms occupying that habitat whether caused by inability of the organisms to remove the water or to the ability of the soil to withhold it