Webster's Revised Unabridged Dictionary · 1913

Clapboard

Clapboard , noun

1.
A narrow board, thicker at one edge than at the other; -- used for weatherboarding the outside of houses. [United States]
2.
A stave for a cask. [English] — Halliwell

Clapboard , transitive verb

To cover with clapboards; as, to clapboard the sides of a house. [United States] — Bartlett