slack

noun

1
a cord or rope or cable that is hanging loosely
he took up the slack
2
the quality of being loose (not taut)
he hadn't counted on the slackness of the rope
3
a soft wet area of low-lying land that sinks underfoot
4
a stretch of water without current or movement
suddenly they were in a slack and the water was motionless
5
a noticeable deterioration in performance or quality
the team went into a slump
a gradual slack in output
6
dust consisting of a mixture of small coal fragments and coal dust and dirt that sifts out when coal is passed over a sieve

1
cause to heat and crumble by treatment with water
slack lime
2
become less in amount or intensity
The storm abated
The rain let up after a few hours
3
make less active or intense
4
become slow or slower
Production slowed
5
make less active or fast
He slackened his pace as he got tired
Don't relax your efforts now
6
release tension on
slack the rope

Also useful for “slack”:Wordle Solver— Five letters — perfect Wordle material