meaning of sheathing
1. Inclosing with a sheath; as, the sheathing leaves of grasses; the sheathing stipules of many polygonaceous plants.
2. That which sheathes.
3. The casing or covering of a ships bottom and sides; the materials for such covering; as, copper sheathing.
4. 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.
5. protective covering consisting, for example, of a layer of boards applied to the studs and joists of a building to strengthen it and serve as a foundation for a weatherproof exterior