Lewis Short
infirmātĭo (noun F) : ōnis. 1. infirmo
* A weakening, invalidating.
* Rerum judicatarum, Cic. Agr. 2, 3, 8; 2, 4, 10.
* Transf., a refuting, disproving: judicatio est, quae ex infirmatione et confirmatione rationis nascitur controversia,Cic. Inv. 1, 13, 18; 2, 21, 62.
Charlton T. Lewis, Charles Short, A Latin Dictionary