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Definitions

slack

[slak] / slæk /
ADJECTIVE
loose, baggy; inactive
Synonyms
STRONGEST
feeble lax leisurely sloppy sluggish
STRONG
dull flimsy laggard limp passive quiet relaxed slow
WEAK
easy flabby flaccid flexible inert infirm not taut quaggy slow-moving soft supine unsteady weak
Antonyms
STRONG
active intelligent lively quick smart strong
WEAK
alert disciplined rigid stiff taut tight
ADJECTIVE
lazy, negligent
Synonyms
STRONGEST
lackadaisical lax lethargic permissive sluggish stagnant
STRONG
delinquent derelict dull idle quiet slow
WEAK
asleep on the job behindhand careless dilatory disregardful dormant easygoing faineant fainéant inactive inattentive indolent inert neglectful not busy quiescent regardless remiss slothful slow-moving tardy
Antonyms
STRONGEST
active energetic lively strict
STRONG
busy careful intelligent quick smart
WEAK
alert disciplined rigid stiff taut tight
NOUN
looseness, excess
Synonyms
STRONG
give leeway play room slackening slowdown
WEAK
slow-up
Antonyms
WEAK
rigidity stiffness tautness tightness

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.