im ‧ per ‧ mis ‧ si ‧ ble /ˌɪmpɜːˈmɪsəb ə l, ˌɪmpɜːˈmɪsɪb ə l $ -ɜːr-/ BrE AmE adjective formal
[ Word Family: noun : ↑ permission , ↑ permit , ↑ permissiveness ; adjective : ↑ permissible ≠ ↑ impermissible , ↑ permissive ; verb : ↑ permit ]
something that is impermissible cannot be allowed OPP permissible