slack
n. uncountable B2 Upper Intermediate US //ˈsɫæk// UK //slˈæk// slack
n. the part of a rope or wire that is loose and not pulled tight. It can also mean extra time or resources that you have available in a schedule.
n. the part of a rope or line that hangs loose; by extension, a lack of tension or a surplus of capacity within a system.
Pull the rope to take up the slack.
The manager hired temporary staff to pick up the slack during the busy holiday season.
In project management, identifying the slack in a schedule allows for more flexible resource allocation without risking the final deadline.
Usage
Often used in the idiomatic phrases 'to take up the slack' or 'to cut someone some slack'.