slack

From Old English slæc (“slack”), from Proto-Germanic *slakaz. For sense of coal dust, compare slag.

• IPA^(key): /slæk/
• Rhymes: -æk

slack (countable and uncountable, plural slacks)

1. (uncountable) Small coal; coal dust.
   • 1905, Colliery Engineer (volume 25, page 107)

     One of the important improvements of recent years has been attained by mixing the peat pulp as it passes through the grinding machine, with other inflammable materials, such as bituminous coal dust, or slack […]

2. (countable) A valley, or small, shallow dell.
3. (uncountable) The part of anything that hangs loose, having no strain upon it.

   the slack of a rope or of a sail

4. (countable) A tidal marsh or shallow, that periodically fills and drains.

• (small coal; coal dust): culm
• (tidal marsh): slough

• (coal dust): nutty slack

slack (comparative slacker, superlative slackest)

1. Lax; not tense; not hard drawn; not firmly extended.

   a slack rope

2. Weak; not holding fast.

   a slack hand

3. Remiss; backward; not using due diligence or care; not earnest or eager.

   slack in duty or service

   • Bible, 2 Peter iii. 9

     The Lord is not slack concerning his promise, as some men count slackness.

4. Not violent, rapid, or pressing.

   Business is slack.

   • 1928, Lawrence R. Bourne, chapter 3, in Well Tackled!‎:

     “They know our boats will stand up to their work,” said Willison, “and that counts for a good deal. A low estimate from us doesn't mean scamped work, but just for that we want to keep the yard busy over a slack time.”

5. (slang, West Indies) vulgar; sexually explicit, especially in dancehall music

• (not violent, rapid, or pressing): slow, moderate, easy

• slacken
• slack-jawed

slack (not comparable)

1. Slackly.

   slack dried hops

slack (third-person singular simple present slacks, present participle slacking, simple past and past participle slacked)

1. To slacken.
   • (Can we date this quote by Robert South?)

     In this business of growing rich, poor men […] should slack their pace.

2. (obsolete) To mitigate; to reduce the strength of.
   • 1590, Edmund Spenser, The Faerie Queene, III.7:

     Ne did she let dull sleepe once to relent, / Nor wearinesse to slack her hast, but fled / Ever alike [...].

3. (followed by “off”) to procrastinate; to be lazy
4. (followed by “off”) to refuse to exert effort
5. To lose cohesion or solidity by a chemical combination with water; to slake.

   Lime slacks.

• skive off

• calks, kcals, lacks