Word Direct Answers

What does "jacket" mean?

Jacket: An outer covering for anything, esp. a covering of some nonconducting material such as wood or felt, used to prevent radiation of heat, as from a steam boiler, cylinder, pipe, etc.

Additional senses

  1. 2.(Mil.) In ordnance, a strengthening band surrounding and reënforcing the tube in which the charge is fired.
  2. 3.A garment resembling a waistcoat lined with cork, to serve as a life preserver; -- called also cork jacket. Blue jacket. (Naut.) See under Blue. -- Steam jacket, a space filled with steam between an inner and an outer cylinder, or between a casing and a receptacle, as a kettle. -- To dust one's jacket, to give one a beating. [Colloq.]
  3. 4.To put a jacket on; to furnish, as a boiler, with a jacket.
  4. 5.To thrash; to beat. [Low]

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