Rodrim was a name mentioned by Beleg Cúthalion in a sharpening spell he casted on his knife. "(...)Glaive of Gaurin whose gleaming stroke did rive the rocks of Rodrim's hall(...)". Rodrim probably means "Caves" or "Domes" and seems to be a placename rather than a personal name. It might be possible that Caves of Rodrim refers to Morgoth's Halls of Thangorodrim.