THESAURUS
slacken
abate, allay, alleviate, anesthetize, appease, arrest, assuage, attemper, attenuate, backpedal, backwater, bank the fire, bate, benumb, block, blunt, bog down, bottle up, brake, chasten, check, clip the wings, come apart, confine, constrain, control, countercheck, curb, cushion, dam up, damp, dampen, de-emphasize, deaden, deaden the pain, decelerate, degenerate, delay, detain, deteriorate, die down, diffuse, dilute, diminish, disimprove, disintegrate, disjoin, disperse, dissolve into chaos, downplay, drag, draw rein, dull, ease, ease matters, ease off, ease up, ebb, extenuate, fall, fall back, foment, free, get worse, give relief, grow worse, hang up, hinder, hold back, hold in check, hold up, impede, inhibit, intercept, interfere, intermeddle, interrupt, intervene, keep back, keep in check, keep within bounds, lag, lax, lay, lenify, lessen, let down, let go, let up, let up on, lighten, loose, loosen, lose ground, lose momentum, lose speed, lull, make late, meddle, mire, mitigate, moderate, modulate, mollify, numb, obstruct, obtund, oppose, pad, palliate, play down, poultice, pour balm into, pour oil on, reduce, reduce the temperature, reef, regress, rein in, relapse, relax, relent, relieve, remit, repress, resist, restrain, retard, retrograde, retrogress, salve, scatter, scotch, set back, sicken, slack, slack off, slack up, slackening, slake, slip back, slow, slow down, slow up, slow-up, smother, snub, sober, sober down, soften, soothe, stay, stifle, stop, stupe, subdue, subside, suppress, take in sail, tame, temper, throttle down, tone down, tune down, unbend, unbrace, underplay, unglue, unlax, unleash, unstick, unstrain, unstring, untighten, untune, unwind, wane, water down, weaken, worsen
ROGET THESAURUS
slacken
Incoherence
VB
make loose, loosen,
slacken, relax, unglue, detach.
Repose
VB
repose, rest, rest and be thankful, take a rest, take one's ease, take it easy, relax, unbend,
slacken, take breath, rest upon one's oars, pause, stay one's hand, lie down, recline, recline on a bed of down, recline on an easy chair, go to rest, go to bed, go to sleep, take a holiday, shut up shop, lie fallow.
Hindrance
VB
hinder, impede, filibuster, impedite, embarrass, keep off, stave off, ward off, obviate, avert, antevert, turn aside, draw off, prevent, forefend, nip in the bud, retard,
slacken, check, let, counteract, countercheck, preclude, debar, foreclose, estop, inhibit, shackle, restrict, obstruct, stop, stay, bar, bolt, lock, block, block up, choke off, belay, barricade, block the way, bar the way, stop the way, forelay, dam up, put on the brake, scotch the wheel, lock the wheel, put a spoke in the wheel, put a stop to, traverse, contravene, interrupt, intercept, oppose, hedge in, hedge round, cut off, inerclude, interpose, interfere, intermeddle, cramp, hamper, clog, clog the wheels, cumber, encumber, incumber, handicap, choke, saddle with, load with, overload, lay, lumber, trammel, tie one's hands, put to inconvenience, incommode, discommode, discompose, hustle, corner, drive into a corner, run foul of, fall foul of, cross the path of, break in upon, thwart, frustrate, disconcert, balk, foil, faze, feaze, feeze, baffle, snub, override, circumvent, defeat, spike guns, spoil, mar, clip the wings of, cripple, put an extinguisher on, damp, dishearten, discountenance, throw cold water on, spoil sport, lay a wet blanket, throw a wet blanket on, cut the ground from under one, take the wind out of one's sails, undermine, be in the way of, stand in the way of, act as a drag, hang like a millstone round one's neck.
Moderation
VB
be moderate, keep within bounds, keep within compass, sober down, settle down, keep the peace, remit, relent, take in sail, moderate, soften, mitigate, temper, accoy, attemper, contemper, mollify, lenify, dulcify, dull, take off the edge, blunt, obtund, sheathe, subdue, chasten, sober down, tone down, smooth down, weaken, lessen, check palliate, tranquilize, pacify, assuage, appease, swag, lull, soothe, compose, still, calm, calm down, cool, quiet, hush, quell, sober, pacify, tame, damp, lay, allay, rebate,
slacken, smooth, alleviate, rock to sleep, deaden, smooth, throw cold water on, throw a wet blanket over, turn off, slake, curb, tame, smooth over, pour oil on the waves, pour oil on the troubled waters, pour balm into, mattre de l'eau dans son vin, go out like a lamb, roar you as gently as any sucking dove.
Slowness
VB
move slowly, creep, crawl, lag, slug, drawl, linger, loiter, saunter, plod, trudge, stump along, lumber, trail, drag, dawdle, grovel, worm one's way, steal along, job on, rub on, bundle on, toddle, waddle, wabble, slug, traipse, slouch, shuffle, halt, hobble, limp, caludicate, shamble, flag, falter, trotter, stagger, mince, step short, march in slow time, march in funeral procession, take one's time, hang fire, retard, relax,
slacken, check, moderate, rein in, curb, reef, strike sail, shorten sail, take in sail, put on the drag, apply the brake, clip the wings, reduce the speed,
slacken speed,
slacken one's pace, lose ground.