as ‧ per ‧ i ‧ ty /æˈsperəti, æˈsperɪti, ə-/ BrE AmE noun [uncountable] formal
[ Date: 1200-1300 ; Language: Old French ; Origin: aspreté , from aspre 'rough' ]
if you speak with asperity, you say something in a way that is rough or severe, showing that you are feeling impatient