noun

1. a short coat, usually with sleeves
2. an outer coating or covering; specif.,
   1. dust jacket
   2. ☆ a cardboard holder for a phonograph record
   3. the metal casing of a bullet
   4. the insulating casing on a pipe or boiler
   5. the skin of a potato, etc.
   6. ☆ a folder or envelope for holding letters or documents

Etymology: ME jaket < OFr jaquette, dim. of jaque < Sp jaco < Ar shakk

transitive verb

1. to put a jacket, or coat, on
2. to cover with a casing, wrapper, etc.