Cut some slack
Meaning
Give someone a break or be lenient.
Usage
Requests patience with a person or process.
Origin & History
Origins and dates here are approximate summaries. Many idioms have disputed or unknown origins, and not every date has been checked against a historical dictionary, so treat specific dates and stories as a starting point rather than a citation.
Sailors let slack out of a rope to ease tension.
Used in nautical writing from the 1800s onward.