tightening
n.the act of making something more firm, closed, or strict. You might hear this when talking about rules or physical objects.
n.the process of making something more secure, restrictive, or less loose. Often refers to the implementation of stricter controls or the physical reduction of slack.
“The tightening of the screws made the chair stable.”
“The government announced a tightening of border controls to improve national security.”
“Economists predict that a further tightening of monetary policy will be necessary to curb rising inflation rates before the end of the fiscal year.”
Often followed by the preposition 'of' to indicate what is being made stricter or firmer.
“However, past promises of tightening gun laws have not prevented recent shootings.”