adj., n., v., & adv.
adj. 1 (of rope etc.) not taut. 2 inactive or sluggish. 3 negligent or remiss. 4 (of tide etc.) neither ebbing nor flowing. 5 (of trade or business or a market) with little happening. 6 loose. 7 Phonet. lax. 8 relaxed, languid.
n. 1 the slack part of a rope (haul in the slack). 2 a slack time in trade etc. 3 colloq. a spell of inactivity or laziness. 4 (in pl.) full-length loosely-cut trousers for informal wear.
v. 1 a tr. & intr. slacken. b tr. loosen (rope etc.). 2 intr. colloq. take a rest, be lazy. 3 tr. slake (lime).
adv. 1 slackly. 2 slowly or insufficiently (dry slack; bake slack). slack hand lack of full control in riding or governing. slack lime slaked lime. slack off 1 loosen. 2 lose or cause to lose vigour. slack rein = slack hand. slack suit US casual clothes of slacks and a jacket or shirt. slack up reduce the speed of a train etc. before stopping. slack water a time near the turn of the tide, esp. at low tide. take up the slack use up a surplus or make up a deficiency; avoid an undesirable lull. slackly adv. slackness n.
[ OE slc f. Gmc ]