The Witch
Despite to popularity of the witch in general [see The Love Witch from 2016], there isn’t a defined witch NPC or monster in AD&D. There are the shamans and witch doctors in the Dungeon Masters Guide and Morgan Le Fay in Deities and Demigods is a sorceress who probably could be a witch, but no stats, levels, or any of the other stuff that would save a lazy dungeon master from having to conjure up a witch on their own.
I haven’t adventured with anyone who played a straight-out witch either. It would be easy enough to turn a magic-user into one. Get find familiar somewhere, stumble into a polymorph scroll that is copied into ye olde spell book, get cloudkill from an unsuspecting local warlock, and next thing that happens, Miss Witch is the next Baga Yaga.
“The Witch” is the song that got me into The Sonics. It was on the Nuggets collection and is almost perfect pre-garage punk: