Un-þurhsceótendlíc

According to the Old English Dictionary:

un-þurhsceótendlíc

adj. Impenetrable :-- Mid ðý unþurhsciótendlícre gescyldnesse gescyld mé inpenetrabili tutela me defende, Lchdm. i. lxix, 5. un-þurhsceotendlic