n. magic, sorcery, spell...

Not long into "The Two Towers" and I have found a word that not only I don't know but is obsolete and hard to find in dictionaries. Eomer describes Gandalf as 'dwimmer-crafty'; apparently dwimmer means magic and sorcery, even occult art, and comes from the Old English gedwimor. The only citation anyone has from it is Tolkien!