sheath
UK: ʃiːθ | US: ʃiːθ
n. a close-fitting cover for a blade or tool
n. a protective covering or structure in biology (e.g., a nerve sheath)
n. a close-fitting dress or garment
The word "sheath" originates from Old English scēath, meaning "a split covering" or "scabbard," derived from the Proto-Germanic skaithiz ("to divide"). This reflects its function as a split or enclosing cover for blades. The root shea- implies separation or protection, while -th forms a noun. Over time, the meaning expanded to include biological and clothing contexts, retaining the core idea of a protective layer.
He slid the dagger back into its leather sheath.
The myelin sheath insulates nerve fibers.
Her elegant sheath dress hugged her figure perfectly.
The sword's sheath was adorned with intricate carvings.
Botanists study the leaf sheath surrounding plant stems.