downhill, adv., adj., & n.
--adv. in a descending direction, esp. towards the bottom of an incline.
--adj.
1 sloping down, descending.
2 declining; deteriorating.
--n.
1 Skiing a downhill race.
2 a downward slope.
3 a decline.

Idiom

go downhill colloq. decline, deteriorate (in health, state of repair, moral state, etc.).

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THESAURUS

downhill

adown, aslant, aslantwise, aslope, at a slant, atilt, below, collapsing, deciduous, decline, declined, declining, declivate, declivitous, declivity, declivous, decurrent, descendant, descending, descent, dip, dipping, down, down south, down-reaching, downcoming, downfalling, downgate, downgoing, downgrade, downline, downright, downsinking, downstairs, downstream, downstreet, downtown, downward, downwards, downwith, drooping, drop, dropping, fall, falling, falling-off, hang, hanging, off plumb, on the descendant, on the downgrade, plummeting, plunging, rakingly, sagging, setting, sinking, slantingly, slantways, slantwise, slaunchways, slopeways, slopingly, submerging, subsiding, tipsily, tottering, tumbledown, upgrade, uphill

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ROGET THESAURUS

downhill

Obliquity

N obliquity, inclination, slope, slant, crookedness, slopeness, leaning, bevel, tilt, bias, list, twist, swag, cant, lurch, distortion, bend, tower of Pisa, acclivity, rise, ascent, gradient, khudd, rising ground, hill, bank, declivity, downhill, dip, fall, devexity, gentle slope, rapid slope, easy ascent, easy descent, shelving beach, talus, monagne Russe, facilis descensus averni.

Descent

N descent, descension, declension, declination, fall, falling, slump, drop, plunge, plummet, cadence, subsidence, collapse, lapse, downfall, tumble, slip, tilt, trip, lurch, cropper, culbute, titubation, stumble, fate of Icarus, avalanche, debacle, landslip, landslide, declivity, dip, hill, rappel, descending, descendent, decurrent, decursive, labent, deciduous, nodding to its fall, downhill, downwards, the bottom fell out.

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