Other forms: slacks
Slack means loose, not pulled tight. A slack rope, the chain is slack, take up the slack.
As a noun, the slack is the loose part: take up the slack, meaning both to tighten a rope and to do work somebody else has stopped doing. Slack also means careless — slack standards, slack about paperwork — and, of trade, quiet: business is slack. Cut somebody some slack means to be less strict with them. Note slacken, the verb, and slacker, meaning somebody who avoids work.
1adjectiveslackLoose; not pulled tight.
“The chain is slack and the whole thing rattles.”
2adjectivecarelessCareless, or quiet in trade.
“Business is slack from about January to March.”
3nounlooseThe loose part of something.
“Take up the slack before you tie it off.”
slack is a state of looseness.
Old English slaec meant lazy as well as loose, and it is related to Latin laxus, which gives English lax and relax. The physical looseness and the moral one have been the same word since the beginning.
Proto-Indo-European
*(s)leg-
Proto-Germanic
*slakaz
Old English
slæc — slack
Middle English
slak
English, today
slack
From Middle English slak, from Old English slæc (“slack”), from Proto-Germanic slakaz. For sense of coal dust, compare slag.
Etymology from Wiktionary, CC BY-SA
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