Jacket
 

jacket
noun1.a short coat2.an outer wrapping or casing; "phonograph records were sold in cardboard jackets"3.(dentistry) dental appliance consisting of an artificial crown for a broken or decayed tooth; "tomorrow my dentist will fit me for a crown"[syn: crown]4.the outer skin of a potato5.the tough metal shell casing for certain kinds of ammunition
verb1.provide with a thermally non-conducting cover; "The tubing needs to be jacketed"2.put a jacket on; "The men were jacketed"