As used in this article and in article four hundred, the following terms shall mean and include:

 1. "Machine-gun" means a weapon of any description, irrespective of size, by whatever name known, loaded or unloaded, from which a number of shots or bullets may be rapidly or automatically discharged from a magazine with one continuous pull of the trigger and includes a sub-machine gun.

 2. "Firearm silencer" means any instrument, attachment, weapon or appliance for causing the firing of any gun, revolver, pistol or other firearms to be silent, or intended to lessen or muffle the noise of the firing of any gun, revolver, pistol or other firearms.

 3. "Firearm" means (a) any pistol or revolver;  or (b) a shotgun having one or more barrels less than eighteen inches in length;  or (c) a rifle having one or more barrels less than sixteen inches in length;  or (d) any weapon made from a shotgun or rifle whether by alteration, modification, or otherwise if such weapon as altered, modified, or otherwise has an overall length of less than twenty-six inches.  For the purpose of this subdivision the length of the barrel on a shotgun or rifle shall be determined by measuring the distance between the muzzle and the face of the bolt, breech, or breechlock when closed and when the shotgun or rifle is cocked;  the overall length of a weapon made from a shotgun or rifle is the distance between the extreme ends of the weapon measured along a line parallel to the center line of the bore.  Firearm does not include an antique firearm.

 4. "Switchblade knife" means any knife which has a blade which opens automatically by hand pressure applied to a button, spring or other device in the handle of the knife.

 5. "Gravity knife" means any knife which has a blade which is released from the handle or sheath thereof by the force of gravity or the application of centrifugal force which, when released, is locked in place by means of a button, spring, lever or other device.

 5-a. "Pilum ballistic knife" means any knife which has a blade which can be projected from the handle by hand pressure applied to a button, lever, spring or other device in the handle of the knife.

 5-b. "Metal knuckle knife" means a weapon that, when closed, cannot function as a set of metal knuckles, nor as a knife and when open, can function as both a set of metal knuckles as well as a knife.

 6. "Dispose of" means to dispose of, give, give away, lease-loan, keep for sale, offer, offer for sale, sell, transfer and otherwise dispose of.

 7. "Deface" means to remove, deface, cover, alter or destroy the manufacturer's serial number or any other distinguishing number or identification mark.

 8. "Gunsmith" means any person, firm, partnership, corporation or company who engages in the business of repairing, altering, assembling, manufacturing, cleaning, polishing, engraving or trueing, or who performs any mechanical operation on, any firearm or machine-gun.

 9. "Dealer in firearms" means any person, firm, partnership, corporation or company who engages in the business of purchasing, selling, keeping for sale, loaning, leasing, or in any manner disposing of, any pistol or revolver.

 10. "Licensing officer" means in the city of New York the police commissioner of that city;  in the county of Nassau the commissioner of police of that county;  in the county of Suffolk the sheriff of that county except in the towns of Babylon, Brookhaven, Huntington, Islip and Smithtown, the commissioner of police of that county;  for the purposes of section 400.01 of this chapter the superintendent of state police; and elsewhere in the state a judge or justice of a court of record having his office in the county of issuance.

 11. "Rifle" means a weapon designed or redesigned, made or remade, and intended to be fired from the shoulder and designed or redesigned and made or remade to use the energy of the explosive in a fixed metallic cartridge to fire only a single projectile through a rifled bore for each single pull of the trigger.

 12. "Shotgun" means a weapon designed or redesigned, made or remade, and intended to be fired from the shoulder and designed or redesigned and made or remade to use the energy of the explosive in a fixed shotgun shell to fire through a smooth bore either a number of ball shot or a single projectile for each single pull of the trigger.

 13. "Cane Sword" means a cane or swagger stick having concealed within it a blade that may be used as a sword or stilletto.

 14. "Chuka stick" means any device designed primarily as a weapon, consisting of two or more lengths of a rigid material joined together by a thong, rope or chain in such a manner as to allow free movement of a portion of the device while held in the hand and capable of being rotated in such a manner as to inflict serious injury upon a person by striking or choking.  These devices are also known as nunchakus and centrifugal force sticks.

 14. "Antique firearm" means:

 Any unloaded muzzle loading pistol or revolver with a matchlock, flintlock, percussion cap, or similar type of ignition system, or a pistol or revolver which uses fixed cartridges which are no longer available in the ordinary channels of commercial trade.

 15. "Loaded firearm" means any firearm loaded with ammunition or any firearm which is possessed by one who, at the same time, possesses a quantity of ammunition which may be used to discharge such firearm.

 15-a. "Electronic dart gun" means any device designed primarily as a weapon, the purpose of which is to momentarily stun, knock out or paralyze a person by passing an electrical shock to such person by means of a dart or projectile.

 15-b. "Kung Fu star" means a disc-like object with sharpened points on the circumference thereof and is designed for use primarily as a weapon to be thrown.

 15-c. "Electronic stun gun" means any device designed primarily as a weapon, the purpose of which is to stun, cause mental disorientation, knock out or paralyze a person by passing a high voltage electrical shock to such person.

 16. "Certified not suitable to possess a self-defense spray device, a rifle or shotgun" means that the director or physician in charge of any hospital or institution for mental illness, public or private, has certified to the superintendent of state police or to any organized police department of a county, city, town or village of this state, that a person who has been judicially adjudicated incompetent, or who has been confined to such institution for mental illness pursuant to judicial authority, is not suitable to possess a self-defense spray device, as defined in section 265.20 of this article, or a rifle or shotgun.

 17. "Serious offense" means (a) any of the following offenses defined in the former penal law as in force and effect immediately prior to September first, nineteen hundred sixty-seven:  illegally using, carrying or possessing a pistol or other dangerous weapon;  making or possessing burglar's instruments;  buying or receiving stolen property;  unlawful entry of a building;  aiding escape from prison;  that kind of disorderly conduct defined in subdivisions six and eight of section seven hundred twenty-two of such former penal law;  violations of sections four hundred eighty-three, four hundred eighty-three-b, four hundred eighty-four-h and article one hundred six of such former penal law; that kind of sodomy or rape which was designated as a misdemeanor;  violation of section seventeen hundred forty-seven-d and seventeen hundred forty-seven-e of such former penal law;  any violation of any provision of article thirty- three of the public health law relating to narcotic drugs which was defined as a misdemeanor by section seventeen hundred fifty-one-a of such former penal law, and any violation of any provision of article thirty-three-A of the public health law relating to depressant and stimulant drugs which was defined as a misdemeanor by section seventeen hundred forty-seven-b of such former penal law.

  (b) any of the following offenses defined in the penal law:  illegally using, carrying or possessing a pistol or other dangerous weapon;  possession of burglar's tools;  criminal possession of stolen property in the third degree; escape in the third degree;  jostling;  fraudulent accosting;  that kind of loitering defined in subdivision three of section 240.35;  endangering the welfare of a child;  the offenses defined in article two hundred thirty-five; issuing abortional articles;  permitting prostitution;  promoting prostitution in the third degree;  stalking in the third degree;  stalking in the fourth degree;   the offenses defined in article one hundred thirty;  the offenses defined in article two hundred twenty.

 18. "Armor piercing ammunition" means any ammunition capable of being used in pistols or revolvers containing a projectile or projectile core, or a projectile or projectile core for use in such ammunition, that is constructed entirely (excluding the presence of traces of other substances) from one or a combination of any of the following:  tungsten alloys, steel, iron, brass, bronze, beryllium copper, or uranium.

 19. "Duly authorized instructor" means (a) a duly commissioned officer of the United States army, navy, marine corps or coast guard, or of the national guard of the state of New York;  or (b) a duly qualified adult citizen of the United States who has been granted a certificate as an instructor in small arms practice issued by the United States army, navy or marine corps, or by the adjutant general of this state, or by the national rifle association of America, a not-for-profit corporation duly organized under the laws of this state;  or (c) by a person duly qualified and designated by the department of environmental conservation under paragraph d of subdivision six of section 11-0713 of the environmental conservation law as its agent in the giving of instruction and the making of certifications of qualification in responsible hunting practices.