alum Copy link Outline I. ComfreyII. A kind of garlic, Plin. 19, 6, 34, § 116 ... • alum (hal-), n., or alus, i, f., a plant. I. Comfrey: Symphytum officinale, Linn.; Plin. 27, 6, 24, § 41; 26, 7, 26, § 42; App. Herb. 59.— II. A kind of garlic, Plin. 19, 6, 34, § 116.