Lewis Short
permansĭo (noun F) : permaneo
* A remaining, persisting (good prose): numquam laudata est in unā sententiā perpetua permansio,Cic. Fam. 1, 9, 21: perseverantia est in ratione bene consideratā stabilis et perpetua permansio,id. Inv. 2, 54, 164; id. Att. 11, 18, 1.
Charlton T. Lewis, Charles Short, A Latin Dictionary