pĕr-infirmus — Lewis & Short
pĕr-infirmus, a, um, adj.,
I very weak or feeble:
si quis perinfirmus est,Cels. 2, 14:
sunt enim levia et perinfirma, quae dicebantur a te,Cic. Fin. 2, 16, 53; Cels. 2, 14 fin.