Slack off means the same as slack .slack off 同 slack
If someone slacks off, Bill comes down hard.
如果有人怠工,比尔就会严厉地加以斥责。
5PHRASE 接手他人不再做的工作;补位提供 To take up the slack or pick up the slack means to do or provide something that another person or organization is no longer doing or providing. 接手他人不再做的工作;补位提供
As major airlines give up less-traveled routes, smaller planes are picking up the slack.