law: 4. Definitions.-
  In this Act, unless the context otherwise requires.-
  (i) "active service", as applied to a person subject to this Act, means the time during which such person-
  (a) is attached to, or forms part of a force which is engaged in operations against an enemy, or
  (b) is engaged in air force operations in, or is on the line of march to, a country or place wholly or partly occupied by an enemy, or (c) is attached to, or forms part of, a force which is in military occupation of any foreign country;
  (ii) "aircraft" includes aeroplanes, balloons, lite balloons, airships, gliders or other machines for flying;
  (iii) "aircraft material" includes any engines, fittings, guns, gear, instruments or apparatus for use in connection with aircraft, and any of its components and accessories and petrol oil, and any other substance used for providing motive power for planes;
  (iv) "Air Force" means officers and airmen who by their commission, warrant, terms of enrolment or otherwise, are liable to render continuously for a term air force service to the Union in every part of the world or any specified part of the world, including persons belonging to1[any Air Force Reserve or the Auxiliary Air Force], when called out on permanent service;
  (v) "Air force custody" means the arrest or confinement of a person according to the usages of the service and includes military or naval custody;
  (vi) "Air Force law" means the law enacted by this Act and the rules made thereunder and includes the usages of the service;
  (vii) "Air Force reward" includes any gratuity or annuity for long service or good conduct, badge pay or pension, and any other Air Force pecuniary reward;
  (viii) "airman" means any person subject to this Act other than an officer;
  (ix) "air officer" means any officer of the Air Force above the rank of group captain;
  (x) "air signal" means any signal intended for the guidance of aircraft, whether given by flag, ground signal, light, wind indicator or in any manner whatsoever;
  (xi) "Chief Legal Adviser" means a person appointed as such by2 [the Chief of the Air staff] to give advice on matters relating to air force law and to perform such other duties of a legal character as may arise in connection therewith;
  (xii) "civil offence" means an offence which is triable by a criminal court;
  (xiii) "civil prison" means any jail or place used for the detention of any criminal prisoner under the Prisons Act, 1894 (9 of 1894), or under any other law for the time being in force;
  3[(xiv) "Chief of the Air Staff" means the officer commanding the Air Force;]
  (xv) "commanding officer" used in relation to a person subject to this Act, means the officer for the time being in command of the unit or detachment to which such person belongs or is attached;
  (xvi) "court-martial" means a court-martial held under this Act;
  (xvii) "criminal court" means a court of ordinary criminal justice in any part of India,4* * * * *;
  (xviii) "enemy" includes all armed mutineers, armed rebels, armed rioters, pirates and any person in arms against whom it is the duty of any person subject to air force law to act;
  (xix) "the Forces" means the regular Army, Navy and Air Force or any part of any one or more of them;
  (xx) "non-commissioned officer" means a person holding a non-commissioned rank or an acting non-commissioned rank in the Air Force, and includes any person holding a non-commissioned rank or an acting non-commissioned rank in 1[any Air Force Reserve or the Auxiliary Air Force] when subject to this Act;
  (xxi) "notification" means a notification published in the Official Gazette;
  (xxii) "offence" means any act or omission punishable under this Act, and includes a civil offence, as hereinbefore defined;
  (xxiii) "officer" means a person commissioned, gazetted or in pay as an officer in the Air Force, and includes-
  (a) an officer of1[any Air Force Reserve or the Auxiliary Air Force] who is for the time being subject to this Act;
  (b) in relation to a person subject to this Act when serving under such conditions as may be prescribed, an officer of the regular Army or the Navy, but does not include a junior commissioned officer, warrant officer, petty officer or non-commissioned officer;
  (xxiv) "prescribed" means prescribed by rules made under this Act;
  (xxv) "provost-marshal" means a person appointed as such under section 108 and includes any of his deputies or assistants or any other person legally exercising authority under him or on his behalf;
  (xxvi) "regulation" includes a regulation made under this Act;
  (xxvii) "superior officer", when used in relation to a person subject to this Act, includes a warrant officer and a non-commissioned officer, and as regards persons serving under such conditions as may be prescribed, an officer, junior commissioned officer, warrant officer, petty officer and non-commissioned officer of the regular Army or the Navy;
  (xxviii) "unit" includes-
  (a) anybody of officers and airmen for which a separate authorised establishment exists;
  (b) any separate body of persons subject to this Act employed on any service and not attached to a unit as aforesaid;
  (c) any other separate body of persons composed wholly or partly of persons subject to this Act, and specified as a unit by the Central Government;
  (xxix) "warrant officer" means a person appointed, gazetted or in pay as a warrant officer of the Air Force and includes an acting warrant officer, a master warrant officer, and a warrant officer of1[any Air Force Reserve or the Auxiliary Air Force] who is for the time being subject to this Act;
  (xxx) 2[all words (except the word "India")] and expressions used herein and defined in the Indian Penal Code (45 of 1860) and not hereinbefore defined shall be deemed to have the meanings respectively assigned to them by that Code.