What's the difference between banister and bannister?

Banister

Definition:

(n.) A stringed musical instrument having a head and neck like the guitar, and its body like a tambourine. It has five strings, and is played with the fingers and hands.

Example Sentences:

(1) Host John Oliver made fun of Tony Abbott, Jaymes Diaz and Stephanie Banister, but my favourite bit was about Peter Dowling’s sexting scandal : You do not pair a penis with red wine.
(2) In the model initially proposed by T. W. Calvert, E. W. Banister, M. V. Savage, and T. Bach (IEEE Trans.
(3) But these men wore western jackets, walked quietly and stayed close to the banister.
(4) Twenty-five patients with congenital uterovaginal agenesis underwent neovaginoplasty according to the McIndoe and Banister technique.
(5) The English ophthalmologist Banister was the first to establish the connection between increased tension of the eyeball and glaucoma.
(6) Like most people, Susanna Reid has legs, but unlike most people, her legs aren't merely articulated flesh banisters used for transporting her from one tiny section of planet to another, but emblematic totems by which she must be judged.
(7) The rooms are set around a series of courtyards with dangling potted plants, and are accessed via stone stairways with wooden banisters.
(8) It turned out to be for the scene where we slide up and down the banister.
(9) Dr Emma Banister is a senior lecturer in consumer research at Manchester Business School.