WordNet sense 1 (a rule for limiting or ending debate in a deliberative body):

cloture, gag law, gag rule

WordNet sense 2 (a Gestalt principle of organization holding that there is an innate tendency to perceive incomplete objects as complete and to close or fill gaps and to perceive asymmetric stimuli as symmetric):

law of closure

WordNet sense 3 (something settled or resolved; the outcome of decision making):

resolution, settlement

WordNet sense 4 (an obstruction in a pipe or tube):

block, blockage, occlusion, stop, stoppage

WordNet sense 5 (approaching a particular destination; a coming closer; a narrowing of a gap):

closing

WordNet sense 6 (termination of operations):

shutdown, closedown