Meaning of half-breadth plan

half'-breadth' plan"

Pronunciation: (haf'bredth', -bretth', -breth', häf'-), [key]
— Naval Archit. Naval Archit.
  1. a diagrammatic plan of one half of the hull of a vessel divided lengthwise amidships, showing water lines, stations, diagonals, and bow and buttock lines. Cf. body plan, sheer plan.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.