STRINGPIECE

Etymology

Noun

stringpiece (plural stringpieces)

(architecture) A long piece of timber, forming a margin or edge of any piece of construction; especially one of the longitudinal pieces supporting a flight or run of stairs.

Source: Wiktionary

String"piece`, n. (Arch.) (a) A long piece of timber, forming a margin or edge of any piece of construction; esp.: (b) One of the longitudinal pieces, supporting the treads and rises of a flight or run of stairs.

Source: Webster’s Unabridged Dictionary 1913 Edition