Webster's Revised Unabridged Dictionary · 1913

Banister

Banister ({not transcribed}) , noun

[A corruption of baluster.]

1.
A baluster.
2.
The balustrade of a staircase. Formerly used in this sense mostly in the plural, now mostly in the singular.
He struggled to ascend the pulpit stairs, holding hard on the banisters. Sir W. Scott. — Sir W. Scott