In this Act the following expressions have the meaning hereby respectively assigned to them, that is to say:—

• “agreement” includes a licence, assignment or assignation;

• “article” includes any substance or material, and any plant, machinery or apparatus, whether affixed to land or not;

• “competent authority” means a Secretary of State, F1...;

• “defence materials” means—

  (a) articles required for the armed forces of the Crown, or for any such supply to the governments of countries outside the United Kingdom, or to the United Nations, as is authorised by the enactments amended by section one of this Act, being articles designed or adapted for the use of armed forces or components of articles so designed or adapted;

  F3(b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

  F2(c) articles required by the Secretary of State for Defence for the production of any such articles as aforesaid

• “production” includes repair, maintenance, testing and development.

This Act shall apply in relation to restrictions subsisting by reason of the existence of copyright in any work as it applies in relation to restrictions imposed by an agreement.