Definition of slack
(Entry 1 of 5)
1
: not using due diligence, care, or dispatch : negligent
2a
: characterized by slowness, sluggishness, or lack of energy
a slack pace
b
: moderate in some quality
especially
: moderately warm
a slack oven
c
: blowing or flowing at low speed
the tide was slack
3a
: not tight or taut
a slack rope
b
: lacking in usual or normal firmness and steadiness : weak
slack muscles slack supervision
4
: wanting in activity : dull
a slack market
5
: lacking in completeness, finish, or perfection
a very slack piece of work
slack
verb
slacked; slacking; slacks
Definition of slack (Entry 2 of 5)
2
: to release tension on : loosen
3a
: to cause to abate
b
: slake sense 3
slack
noun (1)Definition of slack (Entry 3 of 5)
1
: cessation in movement or flow
2
: a part of something that hangs loose without strain
take up the slack of a rope
3
: trousers especially for casual wear
—usually used in plural
4
: a dull season or period
5a
: a part that is available but not used
some slack in the budget
b
: a portion (as of labor or resources) that is required but lacking
hired a temp to take up the slack
6
: additional leeway or relief from pressure
—usually used with cut refused to cut me some slack on the schedule
slack
noun (2)Definition of slack (Entry 4 of 5)
dialectal, England
: a pass between hills
slack
noun (3)Definition of slack (Entry 5 of 5)
: the finest screenings of coal produced at a mine unusable as fuel unless cleaned
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Merriam-Webster unabridged
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Time Traveler for slack
The first known use of slack was before the 12th century
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