Sheathing

Webster's Dictionary of the English Language

·noun That which sheathes.

II. Sheathing ·noun The casing or covering of a ship's bottom and sides; the materials for such covering; as, copper sheathing.

III. Sheathing (·p.pr. & ·adj) Inclosing with a sheath; as, the sheathing leaves of grasses; the sheathing stipules of many polygonaceous plants.

IV. Sheathing ·noun The first covering of boards on the outside wall of a frame house or on a timber roof; also, the material used for covering; ceiling boards in general.