prŏpĕrantĭa, ae, f. [propero],
a hastening , haste (very rare; not in Cic. or Caes.): ex tantā properantiā, Sall. J. 36, 3: periculum ex properantiā, Tac. A. 12, 20.
properantia ae, f propero, a hastening, haste : ex tantā properantiā, S.: periculum ex properantiā...
An Elementary Latin Dictionary