(1) This Act may be cited as the Northern Ireland Constitution Act 1973.
(2) In this Act—
“ the appointed day ” means the day appointed under section 2 above for the commencement of Part II of this Act;
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“ enactment ” includes an enactment of the Parliament of Northern Ireland;
“ functions ” includes powers and duties;
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“ Northern Ireland ” has the same meaning as for the purposes of the Government of Ireland Act 1920;
“ Northern Ireland executive authorities ” has the meaning given in section 7(6) above;
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(4) Any reference in this Act to any enactment is a reference to that enactment as amended by, and includes a reference to that enactment as extended or applied by, any other enactment including this Act.
(5) Part I of this Act and, except where otherwise stated, Parts IV and V of this Act shall come into force at the passing of this Act.
(6) Part III of this Act shall come into force on a day specified in an order made by the Secretary of State by statutory instrument, and different days may be specified under this subsection for different provisions of Part III.