- A witch, sorceress, or enchantress; also, a wizard.(Obs)"Silenus] that old hag." [Golding.]
- An ugly old woman.
- A fury; a she-monster.
- [Zoöl] 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.
- [Zoöl] The hagdon or shearwater.
- An appearance of light and fire on a horse's mane or a man's hair.
Etymology: OE. hagge hegge, witch, hag, AS. hægtesse; akin to OHG. hagazussa, G. hexe, D. heks, Dan. hex, Sw. häxa. The first part of the word is prob. the same as E. haw hedge, and the orig. meaning was perh., wood woman, wild woman. √12