The definition of a banister is the long support that runs along the side of a staircase.
(noun)An example of a banister is a wooden rail to the side of a staircase that can be held for support.
See banister in Webster's New World College Dictionary
noun
Origin: altered < baluster
See banister in American Heritage Dictionary 4
also ban·nis·ter
nounOrigin:
Origin: Variant of baluster
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