Searu-grim

According to the Old English Dictionary:

searu-grim

adj. Fierce in arms or skilfully fierce, having fierceness accompanied by skill:--Gif ðín hige wǽre swá searogrim swá ðú self talast if thy spirit had been as cunningly fierce (?) as thyself reckons, Beo. Th. 1192; B. 594. Cf. searu-céne. searu-grim