slack

Concise Oxford English Dictionary © 2008 Oxford University Press:
slack1

▶adjective

• 1 not taut or held tightly in position; loose.

• 2 (of business or trade) not busy; quiet.

• 3 careless, lazy, or negligent.

• 4 W. Indian lewd or promiscuous.

• 5 (of a tide) neither ebbing nor flowing.

▶noun

• 1 the part of a rope or line which is not held taut.

• 2 (slacks) casual trousers.

• 3 informal a period of inactivity or laziness.

▶verb

• 1 loosen (something, especially a rope).

• 2 (slack off/up) decrease in intensity or speed.

• 3 Brit. informal work slowly or lazily.

• 4 slake (lime).

– phrases
cut someone some slack N. Amer. informal allow someone some leeway in their conduct.
take (or pick) up the slack improve the use of resources to avoid an undesirable lull in business.

– derivatives
slacken verb,
slackly adverb,
slackness noun.

– origin OE slæc ‘inclined to be lazy, unhurried’, of Gmc origin.

Concise Oxford English Dictionary © 2008 Oxford University Press:
slack2

▶noun coal dust or small pieces of coal.

– origin ME: prob. from Low Ger. or Du.