Definition of jacket

< jacked

Jack Frost >

jack·et    (jkt) KEY 

NOUN:

1. A short coat usually extending to the hips.
2. An outer covering or casing, especially:
   1. The skin of a potato.
   2. The dust jacket of a book or phonograph record.
   3. An insulation covering for a steam pipe, wire, boiler, or similar part.
   4. An open envelope or folder for filing papers.
   5. The outer metal shell or case of a bullet.

TRANSITIVE VERB:
jack·et·ed, jack·et·ing, jack·ets

To supply or cover with a jacket.

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ETYMOLOGY:
Middle English jaket, from Old French jaquet, diminutive of jaque, short jacket, tunic, from jacques, nickname for French peasants (from the name Jacques; see jack), or from Old Catalan jaco (perhaps from Arabic akk, mailcoat)

OTHER FORMS:
jacket·ed(Adjective)