prohibendus

Future passive participle (gerundive) of prohibeō (“forbid”).

prohibendus (feminine prohibenda, neuter prohibendum); first/second-declension participle

1. which is to be held back, which is to be kept off, which is to be restrained, which is to be averted; which is to be prevented, which is to be hindered
2. which is to be forbidden, which is to be prohibited
3. which is to be kept, which is to be preserved, which is to be defended, which is to be protected

First/second-declension adjective.