bal·us·ter / ˈbaləstər/ • n. a short pillar or column, typically decorative in design, in a series supporting a rail or coping. ∎  [as adj.] (of a furniture leg or other decorative item) having the form of a baluster.ORIGIN: early 17th cent.: from French balustre, from Italian balaustro, from balaust(r)a ‘wild pomegranate flower’ (via Latin from Greek balaustion), so named because part of the pillar resembles the curving calyx tube of the flower.

baluster. Upright support in a balustrade: it may be a square, circular, turned, or ornamented bar or rod, very small in thickness (as in a stair balustrade); it can be a miniature column; or it can be the bellied, bulbed type of colonnette (columella), with base, shaft, and capital, circular, polygonal, or square on plan, with elaborate profiles, in some cases given distinctive features depending on which Order is used elsewhere. The thickest part of a baluster is called the belly, and the thin part the sleeve. Banister is sometimes used instead of baluster, while banisters signifies a balustrade.See Illustrations Stair.

baluster one of a series of short moulded shafts supporting a coping or rail. XVII. — F. balustre — It. balaustro, ult. f. L. balaustrum blossom of the wild pomegranate (which the moulded pillar resembled) — Gr. balaústion. See BANISTER.
So balustrade XVII. — F. — It. balaustrata.