Hag n.
 1. A witch, sorceress, or enchantress; also, a wizard. [Obs.] “[Silenus] that old hag.”
 2. An ugly old woman.
 3. A fury; a she-monster.
 4. Zool. An eel-like marine marsipobranch (Myxine glutinosa), allied to the lamprey. It has a suctorial mouth, with labial appendages, and a single pair of gill openings. It is the type of the order Hyperotreta.  Called also hagfish, borer, slime eel, sucker, and sleepmarken.
 5. Zool. The hagdon or shearwater.
 6. An appearance of light and fire on a horse's mane or a man's hair.
 Hag moth Zool., a moth (Phobetron pithecium), the larva of which has curious side appendages, and feeds on fruit trees.
 Hag's tooth Naut., an ugly irregularity in the pattern of matting or pointing.