A short upper garment, extending downward to the hips; a short coat without skirts. [1913 Webster]
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. [1913 Webster]
In ordnance, a strengthening band surrounding and reënforcing the tube in which the charge is fired. [1913 Webster]
A garment resembling a waistcoat lined with cork, to serve as a life preserver; -- called also cork jacket. [1913 Webster]

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.]

jacket, v. t.

To put a jacket on; to furnish, as a boiler, with a jacket. [1913 Webster]
To thrash; to beat. [1913 Webster]

top

OXFORD DICTIONARY

jacket, n. & v.
--n.
1 a a sleeved short outer garment. b a thing worn esp. round the torso for protection or support (life-jacket).
2 a casing or covering, e.g. as insulation round a boiler.
3 = dust-jacket.
4 the skin of a potato, esp. when baked whole.
5 an animal's coat.
--v.tr. (jacketed, jacketing) cover with a jacket.

Idiom

jacket potato a baked potato served with the skin on.

Etymology

ME f. OF ja(c)quet dimin. of jaque JACK(2)

top

THESAURUS

jacket

Eton jacket, Leatherette, Leatheroid, Mao jacket, Smyth sewing, backing, bandage, bandaging, bark, bibliopegy, binder, binder board, binding, blazer, blouse, body coat, bolero, bomber jacket, bonnet, book cloth, book cover, book jacket, bookbinding, bookcase, boot, bran, breech, cap, capsule, capuchin, car coat, case, casemaking, casing-in, chaff, chaqueta, chesterfield, claw hammer, claw-hammer coat, cloak, coat, coif, collating, collating mark, corn shuck, cornhusk, cover, cutaway coat, cuticle, dermis, dinner jacket, doublet, dress coat, duffel, dust cover, dust jacket, envelope, envelopment, fell, fingertip coat, fitted coat, fleece, flesh, folding, footband, frock, frock coat, fur, furring, gathering, gift wrapping, gluing-off, gown, greatcoat, hard binding, hat, headband, hide, hood, hull, husk, imitation fur, imitation leather, integument, jerkin, jumper, jupe, leather, leather paper, library binding, lining, lining-up, loden coat, mackinaw, mantle, mechanical binding, mess jacket, midicoat, monkey jacket, niggerhead, outer layer, outer skin, overcoat, palea, parka, pea jacket, peel, pelt, peltry, perfect binding, plastic binding, pod, rawhide, reefer, rind, rounding, sack, saddle stitching, san benito, sewing, sheath, shell, shirt, shoe, shuck, side sewing, signature, ski jacket, skin, skins, sleeve waistcoat, slipcase, slipcover, smashing, smoking jacket, sock, soft binding, spiketail coat, spiral binding, stamping, stapling, stocking, swallowtail, tabard, tail coat, tailband, tails, tegument, tipping, topcoat, trimming, vair, watch coat, windbreaker, wire stitching, woolly, wrap, wrapper, wrapping

For further exploring for "jacket" in Webster Dictionary Online