"slacks" in the noun sense

1. slack

dust consisting of a mixture of small coal fragments and coal dust and dirt that sifts out when coal is passed over a sieve

2. slump, slack, drop-off, falloff, falling off

a noticeable deterioration in performance or quality

"the team went into a slump"

"a gradual slack in output"

"a drop-off in attendance"

"a falloff in quality"

3. slack, slack water

a stretch of water without current or movement

"suddenly they were in a slack and the water was motionless"

4. mire, quagmire, quag, morass, slack

a soft wet area of low-lying land that sinks underfoot

5. slack, slackness

the quality of being loose (not taut

"he hadn't counted on the slackness of the rope"

6. slack

a cord or rope or cable that is hanging loosely

"he took up the slack"

"slacks" in the verb sense

1. slack

avoid responsibilities and work, be idle

2. slack

be inattentive to, or neglect

"He slacks his attention"

3. slack

release tension on

"slack the rope"

4. slack, slacken, slack up, relax

make less active or fast

"He slackened his pace as he got tired"

"Don't relax your efforts now"

5. slow, slow down, slow up, slack, slacken

become slow or slower

"Production slowed"

6. slake, abate, slack

make less active or intense

7. abate, let up, slack off, slack, die away

become less in amount or intensity

"The storm abated"

"The rain let up after a few hours"

8. slack, slake

cause to heat and crumble by treatment with water

"slack lime"

Source: WordNet® (An amazing lexical database of English)

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