[1] : The Collaborative International Dictionary of English v.0.48

gin \gin\ gi^n, v. i. imp.  p. p. gan ga^n, gon
   go^n, or gun gu^n; p. pr.  vb. n. ginning. oe.
   ginnen, as. ginnan in comp., prob. orig., to open, cut
   open, cf. ohg. inginnan to begin, open, cut open, and prob.
   akin to as. gimacnan to yawn, and e. yawn. root31. see
   yawn, v. i., and cf. begin.
   to begin; -- often followed by an infinitive without to; as,
   gan tell. see gan. obs. or archaic "he gan to pray."
   --chaucer.
   1913 webster
see also:
gan gon gun ginning yawn begin 

[2] : The Collaborative International Dictionary of English v.0.48

gun \gun\ gu^n, n. oe. gonne, gunne; of uncertain origin;
   cf. ir., gael.,  ll. gunna, w. gum; possibly like cannon
   fr. l. canna reed, tube; or abbreviated fr. of. mangonnel, e.
   mangonel, a machine for hurling stones.
   1. a weapon which throws or propels a missile to a distance;
      any firearm or instrument for throwing projectiles,
      consisting of a tube or barrel closed at one end, in which
      the projectile is placed, with an explosive charge such
      as guncotton or gunpowder behind, which is ignited by
      various means. pistols, rifles, carbines, muskets, and
      fowling pieces are smaller guns, for hand use, and are
      called small arms. larger guns are called cannon,
      ordnance, fieldpieces, carronades, howitzers, etc.
      see these terms in the vocabulary.
      1913 webster

            as swift as a pellet out of a gunne
            when fire is in the powder runne.     --chaucer.
      1913 webster

            the word gun was in use in england for an engine to
            cast a thing from a man long before there was any
            gunpowder found out.                  --selden.
      1913 webster

   2. mil. a piece of heavy ordnance; in a restricted sense, a
      cannon.
      1913 webster

   3. pl. naut. violent blasts of wind.
      1913 webster

   note: guns are classified, according to their construction or
         manner of loading as rifled or smoothbore,
         breech-loading or muzzle-loading, cast or
         built-up guns; or according to their use, as field,
         mountain, prairie, seacoast, and siege guns.
         1913 webster

   armstrong gun, a wrought iron breech-loading cannon named
      after its english inventor, sir william armstrong.

   big gun or great gun, a piece of heavy ordnance; hence
      fig., a person superior in any way; as, bring in the big
      guns to tackle the problem.

   gun barrel, the barrel or tube of a gun.

   gun carriage, the carriage on which a gun is mounted or
      moved.

   gun cotton chem., a general name for a series of
      explosive nitric ethers of cellulose, obtained by steeping
      cotton in nitric and sulphuric acids. although there are
      formed substances containing nitric acid radicals, yet the
      results exactly resemble ordinary cotton in appearance. it
      burns without ash, with explosion if confined, but quietly
      and harmlessly if free and open, and in small quantity.
      specifically, the lower nitrates of cellulose which are
      insoluble in ether and alcohol in distinction from the
      highest pyroxylin which is soluble. see pyroxylin, and
      cf. xyloidin. the gun cottons are used for blasting and
      somewhat in gunnery: for making celluloid when compounded
      with camphor; and the soluble variety pyroxylin for
      making collodion. see celluloid, and collodion. gun
      cotton is frequenty but improperly called
      nitrocellulose. it is not a nitro compound, but an ester
      of nitric acid.

   gun deck. see under deck.

   gun fire, the time at which the morning or the evening gun
      is fired.

   gun metal, a bronze, ordinarily composed of nine parts of
      copper and one of tin, used for cannon, etc. the name is
      also given to certain strong mixtures of cast iron.

   gun port naut., an opening in a ship through which a
      cannon's muzzle is run out for firing.

   gun tackle naut., the blocks and pulleys affixed to the
      side of a ship, by which a gun carriage is run to and from
      the gun port.

   gun tackle purchase naut., a tackle composed of two
      single blocks and a fall. --totten.

   krupp gun, a wrought steel breech-loading cannon, named
      after its german inventor, herr krupp.

   machine gun, a breech-loading gun or a group of such guns,
      mounted on a carriage or other holder, and having a
      reservoir containing cartridges which are loaded into the
      gun or guns and fired in rapid succession. in earlier
      models, such as the gatling gun, the cartridges were
      loaded by machinery operated by turning a crank. in modern
      versions the loading of cartidges is accomplished by
      levers operated by the recoil of the explosion driving the
      bullet, or by the pressure of gas within the barrel.
      several hundred shots can be fired in a minute by such
      weapons, with accurate aim. the gatling gun, gardner
      gun, hotchkiss gun, and nordenfelt gun, named for
      their inventors, and the french mitrailleuse, are
      machine guns.

   to blow great guns naut., to blow a gale. see gun, n.,
      3.
      1913 webster +pjc
see also:
small arms cannon ordnance fieldpieces carronades howitzers 
rifled smoothbore breech-loading muzzle-loading cast 
built-up guns field mountain prairie seacoast 
siege guns armstrong gun big gun great gun gun barrel 
gun carriage gun cotton pyroxylin xyloidin celluloid 
collodion nitrocellulose gun deck deck gun fire 
gun metal gun port gun tackle gun tackle purchase krupp gun 
machine gun gatling gun gardner gun hotchkiss gun nordenfelt gun 
mitrailleuse to blow great guns gun 

[3] : The Collaborative International Dictionary of English v.0.48

gun \gun\, v. i.
   to practice fowling or hunting small game; -- chiefly in
   participial form; as, to go gunning.

[4] : WordNet (r) 2.0

gun
     n 1: a weapon that discharges a missile at high velocity
          especially from a metal tube or barrel
     2: large but transportable armament syn: artillery, heavy
        weapon, ordnance
     3: a person who shoots a gun as regards their ability syn: gunman
     4: a professional killer who uses a gun syn: gunman, gunslinger,
         hired gun, gun for hire, triggerman, hit man, hitman,
         torpedo, shooter
     5: a hand-operated pump that resembles a gun; forces grease
        into parts of a machine syn: grease-gun
     6: a pedal that controls the throttle valve; "he stepped on the
        gas" syn: accelerator, accelerator pedal, gas pedal,
         gas, throttle
     7: the discharge of a gun as signal or as a salute in military
        ceremonies; "a twenty gun salute"
     v : shoot with a gun
     also: gunning, gunned
see also:
artillery heavy weapon ordnance gunman gunslinger hired gun 
gun for hire triggerman hit man hitman torpedo 
shooter grease-gun accelerator accelerator pedal gas pedal 
gas throttle gunning gunned 

[5] : Moby Thesaurus II by Grady Ward, 1.0

334 moby thesaurus words for "gun":
   aa gun, armstrong, bar, bb gun, benet-mercie, beretta, big bertha,
   bren, bren gun, browning, cain, colt, garand, garand rifle,
   garling, gatling, gatling gun, hotchkiss, krupp, lancaster,
   lee-enfield, lee-metford, lewis, lewis gun, long tom, luger,
   mannlicher, marlin, martini-henry, mauser, maxim, minie, mossberg,
   nimrod, oerlikon, paixhans, parrott, remington, savage,
   smith and wesson, snider, spandau, springfield, stevens,
   thompson submachine gun, vickers, vickers-maxim, webley-scott,
   winchester, y-gun, adventurer, air gun, antiaircraft gun,
   antitank gun, antitank rifle, apache, archer, arquebus, arrest,
   artillerist, artilleryman, assassin, assassinator, atom gun,
   atomic cannon, atomic gun, automatic, automatic pistol, barrel,
   bazooka, beat, bell, bloodletter, bloodshedder, blowgun, blowpipe,
   blunderbuss, bolt, bolt-action rifle, bomb thrower, bombard,
   bombardier, bomber, bowman, bowshot, bravo, breech, breechloader,
   brown bess, bruiser, bulldog, bullet, burker, burp gun, butcher,
   butt, button man, caliver, cane gun, cannibal, cannon, cannoneer,
   carabineer, carbine, carronade, chamber, charge, chase, chassepot,
   check, checkmate, cock, condottiere, course, crack shot, culverin,
   cutoff, cutthroat, cylinder, dart gun, dead shot, dead stop,
   deadeye, deadlock, desperado, detonate, detonation, discharge, dog,
   drive, drop, eject, ejection, end, endgame, ending, eradicator,
   escopeta, executioner, exterminator, falcon, falconet, fell,
   field gun, fieldpiece, final whistle, fire, fire off, firearm,
   firelock, flamethrower, flintlock, flush, follow the hounds,
   forty-five, forty-four, fowl, fowling piece, free lance, full stop,
   fusil, fusillade, garroter, gat, go hunting, good shot, goon,
   gorilla, grinding halt, gun carriage, gun for, gunfire, gunman,
   gunner, gunsel, gunshot, gunslinger, hackbut, halt, hammer,
   handgun, harpoon gun, harquebus, hatchet man, hawk, head-hunter,
   heater, hedgehog, hellion, hired gun, hired killer, hireling, hit,
   hit man, holy terror, homicidal maniac, homicide, hood, hoodlum,
   hooligan, horse pistol, hound, howitzer, hunt, hunt down, hunter,
   jack, jacklight, killer, let fly, let off, load, lock, lockout,
   machine gun, machine gunner, machine pistol, magazine, man-eater,
   man-killer, manslayer, marksman, markswoman, massacrer, matador,
   matchlock, mercenary, mortar, mountain gun, mug, mugger, murderer,
   muscle man, musket, musketeer, musketoon, muzzle, muzzle-loader,
   needle gun, peashooter, pedrero, pelt, pepper, pesticide, petronel,
   pick off, piece, pistol, plug, plug-ugly, poison, poisoner,
   pom-pom, popgun, pot, potshoot, potshot, prime,
   professional killer, prowl after, receiver, repeater, revolver,
   riddle, ride to hounds, rifle, rifleman, rod, rodman, roughneck,
   run, salvo, sawed-off shotgun, sear, semiautomatic, sharpshooter,
   shikar, shoot, shoot at, shoot down, shooter, shooting iron, shot,
   shotgun, sight, sit-down strike, six-gun, six-shooter, skysweeper,
   slaughterer, slayer, snipe, sniper, soldier of fortune, sport,
   spray, stalemate, stalk, stand, standoff, standstill, start, stay,
   still-hunt, stock, stoneshot, stop, stoppage, strangler, strike,
   strong-arm man, submachine gun, swivel, take a potshot,
   targetshooter, tattoo, terror, thirty-thirty, thirty-two, thug,
   torpedo, tough, toxophilite, track, trail, trapshooter, trigger,
   trigger man, ugly customer, volley, walkout, wind-gun,
   work stoppage, zip gun

[6] : Jargon File (4.3.1, 29 Jun 2001)

gun vt. its, now rare: from the `:gun' command to forcibly terminate
   a program or job computer, not career. "some idiot left a background
   process running soaking up half the cycles, so i gunned it." usage: now
   rare. compare can, blammo.


see also:
can blammo 

[7] : The Free On-line Dictionary of Computing (27 SEP 03)

gun
     
         its, from the ":gun" command to forcibly
        terminate a program or job computer, not career.  "some
        idiot left a background process running soaking up half the
        cycles, so i gunned it."
     
        compare can.
     
        1995-02-27
     
     
see also:
its can 

Gun >> G Words
Gun, definition of term: Gun
gun_pag1.html

Gun Control >> G Words
Gun Control, definition of term: Gun Control
gun+control_pag1.html

Gun Barrel >> G Words
Gun Barrel, definition of term: Gun Barrel
gun+barrel_pag1.html

Bb Gun >> B Words
Bb Gun, definition of term: Bb Gun
bb+gun_pag1.html

Field Gun >> F Words
Field Gun, definition of term: Field Gun
field+gun_pag1.html

Gatling Gun >> G Words
Gatling Gun, definition of term: Gatling Gun
gatling+gun_pag1.html

Gun Barrel City >> G Words
Gun Barrel City, definition of term: Gun Barrel City
gun+barrel+city_pag1.html