A sheath is a protective case for a knife or a sword. The most exciting part of a staged sword fight might be the moment when the hero pulls his weapon out of its sheath.

A sheath is also a dress that is straight, fitted, and simple. You might advise your Aunt Martha to choose a sheath dress for her third wedding, instead of the white lace gown with the long train. The word sheath most likely comes from the Old English scēath, meaning a divide or a split, like the split piece of wood which originally served as a sword's sheath.

Definitions of sheath
  1. noun
    a protective covering (as for a knife or sword)
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    aglet, aiglet
    metal or plastic sheath over the end of a shoelace or ribbon
    cot, fingerstall
    a sheath worn to protect a finger
    a sheath (usually leather) for carrying a handgun
    a sheath for a sword or dagger or bayonet
    shoulder holster
    a holster worn over your shoulder so a gun can be concealed under your jacket
    type of:
    protection, protective cover, protective covering
    a covering that is intend to protect from damage or injury
  2. noun
    an enveloping structure or covering enclosing an animal or plant organ or part
    synonyms: case
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    outer sheath of the pupa of certain insects
    a hard protective sheath (as secreted by certain protoctists, for example)
    medullary sheath, myelin sheath
    a layer of myelin encasing (and insulating) the axons of medullated nerve fibers
    neurilemma, neurolemma
    thin membranous sheath around a nerve fiber
    outer membranous covering of some fruits or seeds
    the husk of an ear of corn
    dry outer covering of a fruit or seed or nut
    cod, pod, seedcase
    the vessel that contains the seeds of a plant (not the seeds themselves)
    a modified leaf or leaflike part just below and protecting an inflorescence
    type of:
    cover, covering, natural covering
    a natural object that covers or envelops
  3. noun
    a dress suitable for formal occasions
    synonyms: cocktail dress
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    type of:
    dress, frock
    a one-piece garment for a woman; has skirt and bodice
Word Family

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