slack

If you slow down at the end of a race, you slack off. When you use slack this way, it means to reduce your speed, to be sluggish, or to be negligent.

If something is loose, it's also said to be slack. A clothesline, for example, is slack if it is just hanging loosely between two trees. If you pull the clothesline tight, you reduce the slack. The root word of slack is the Old English word slæc, which means loose or careless. When you scold your friend for being careless about his responsibilities, you can say, "Pick up the slack!"

Primary Meanings of slack

1.
adjnv
not tense or taut
the quality of being loose (not taut)
release tension on
2.
adjnv
lacking in rigor or strictness
a noticeable deterioration in performance or quality
avoid responsibilities and work, be idle
3.
nadj
a stretch of water without current or movement
flowing with little speed as e.g. at the turning of the tide
4.
n
a soft wet area of low-lying land that sinks underfoot
5.
n
dust consisting of a mixture of small coal fragments and coal dust and dirt that sifts out when coal is passed over a sieve
6.
v
cause to heat and crumble by treatment with water
Full Definitions of slack
1

adj not tense or taut

slack and wrinkled skin”
slack sails”
“a slack rope”
Synonyms:
loose
lax
lacking in strength or firmness or resilience

n the quality of being loose (not taut)

Synonyms:
slackness
Type of:
looseness, play
movement or space for movement

n a cord or rope or cable that is hanging loosely

“he took up the slack
Type of:
cord
a line made of twisted fibers or threads

v release tension on

slack the rope”
Type of:
loose, loosen
make loose or looser

v make less active or fast

Synonyms:
relax, slack up, slacken
Type of:
decrease, lessen, minify
make smaller

v make less active or intense

Synonyms:
abate, slake
Type of:
decrease, lessen, minify
make smaller

v become less in amount or intensity

Synonyms:
abate, die away, let up, slack off
Type of:
decrease, diminish, fall, lessen
decrease in size, extent, or range

v become slow or slower

Synonyms:
slacken, slow, slow down, slow up
Type of:
weaken
become weaker
2

adj lacking in rigor or strictness

slack in maintaining discipline”
Synonyms:
lax
negligent
characterized by neglect and undue lack of concern

n a noticeable deterioration in performance or quality

“a gradual slack in output”
Synonyms:
drop-off, falling off, falloff, slump
Type of:
declension, decline in quality, deterioration, worsening
process of changing to an inferior state

v avoid responsibilities and work, be idle

Type of:
fiddle, goldbrick, shirk, shrink from
avoid (one's assigned duties)

v be inattentive to, or neglect

“He slacks his attention”
Type of:
neglect
fail to attend to
3

n a stretch of water without current or movement

“suddenly they were in a slack and the water was motionless”
Synonyms:
slack water
Type of:
stretch
a large and unbroken expanse or distance

adj flowing with little speed as e.g. at the turning of the tide

slack water”
Synonyms:
standing
(of fluids) not moving or flowing
4

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

Synonyms:
mire, morass, quag, quagmire
Type of:
bog, peat bog
wet spongy ground of decomposing vegetation; has poorer drainage than a swamp; soil is unfit for cultivation but can be cut and dried and used for fuel
5

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

Type of:
debris, detritus, dust, junk, rubble
the remains of something that has been destroyed or broken up
6

v cause to heat and crumble by treatment with water

slack lime”
Synonyms:
slake
Types:
air-slake
alter by exposure to air with conversion at least in part to a carbonate
Type of:
hydrate
cause to be hydrated; add water or moisture to

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