In my opinion, the term “Witch” is a misnomer for the entity that haunted the Bell family.  A far better term for this entity would be goblin.  The goblin-type behavior, defined below, seems to reasonably match the behavior described in most of the Bell Witch folklore.  The biggest difference is the speech capability of the entity.  To the best of my knowledge, stories of supernatural entities that have the power of fluent speech are very rare.

The Encyclopedia of Ghosts and Spirits provides the following definition:

GOBLIN:  Generally, any type of small, hideous, mischievous or evil spirit. In some cultures, putting the prefix "hob" in front of the word differentiates them from mean-spirited to helpful and kind spirits, al­though still full of mischief. The Puritans, however, did not subscribe to this notion, and used the term to describe any nasty little creatures.

In French folklore, goblins are wandering spirits who attach themselves to households, where they alternately help and plague the residents, depending on their whims. Goblins are believed to live in grot­toes, but are attracted to homes that have beautiful children and lots of wine. When they move in, they help by doing household chores at night and by disciplining children giving them presents when they are good and punishing them when they are naughty.  Goblins have an unpredictable, mischievous nature. On some nights, instead of doing chores, they will keep everyone awake by banging pots and pans, moving furniture, knocking on walls and doors, and snatching bedclothes off sleeping persons.  Goblins who become tiresome can be persuaded to leave by scattering flaxseed on the floor.  The sprites get tired of cleaning it up every night and decide to depart for more hospitable surrounding.

Goblins are similar to brownies, household spirits in England and Scotland, Domoviks in Russia, and other sprites in other countries.  In Germany, they are called Kobalds, and they work industriously in the mines; they are sometimes thought of as earth elementals.

Goblins in general have become associated with ALL HALLOWS EVE and are said to roam that night when the veil is thinnest between the world of the living and the world of the dead.