下り坂|くだりざかkudarizaka[0]heiban (flat)

1. noundownhill; downward slope; descent
   丘おかは川かわのほうまで下り坂くだりざかになっています。↗

   The hill slopes downward to the river.
2. noundecline; waning; ebb; (going) downhill

• Related低下ていかNeutralFor drops in figures or ability, as in 「視力の低下」; neutral and objective, whereas 「下り坂」 carries the image of going down a slope.
• Related下落げらくNeutralFor falling prices and market quotations, as in 「株価の下落」; it centers on value, while 「下り坂」 speaks of momentum weakening overall.
• Related衰退すいたいNeutralFor long-term decline of industries or power, as in 「産業の衰退」; 「下り坂」 is more figurative and also covers weather turning worse.
• Related下降かこうNeutralAn objective word for position or figures moving down, as in 「気温の下降」; unlike 「下り坂」 it lacks the metaphor of a downward trend.
• Related衰えおとろえNeutralFor weakening strength, ability or momentum, as in 「体力の衰え」 and 「国力の衰え」; 「下り坂」 stresses the process of sliding downhill.
• Related低落ていらくWrittenWritten/formal prose for falls in value, prices or popularity, and not much used; 「下り坂」 is both more common and more vivid.
• RelatedさがりNeutralMeans lowering or hanging down, also food offerings removed from the altar; usually seen inside compounds such as 「値下がり」, and never refers to a slope.
• Related衰微すいびWrittenWritten/formal prose for something once flourishing now fading, with a withering feel; 「下り坂」 can mean still on the way down, not yet faded.
• Related凋落ちょうらくWrittenOriginally of flowers falling; a written/formal word for a family or power in decline, tinged with pathos, which 「下り坂」 does not carry.
• Related落ち込みおちこみNeutralFor dips in figures or low spirits, as in 「需要の落ち込み」; frequent in news and economic reports, while 「下り坂」 never refers to mood.
• Antonym上り坂のぼりざかNeutralThe antonym: an uphill road, or momentum gradually rising, as in 「人気が上り坂」; it stands in direct contrast to 「下り坂」.

Use 「下り坂」 for a downhill road and, figuratively, for fortunes, weather or popularity heading down, as in 「天気は下り坂」. For plain drops in figures pick 「低下」 or 「下降」, for prices 「下落」, for long-term decline 「衰退」, for weakening strength 「衰え」, for dips in demand or mood 「落ち込み」. 「低落」「衰微」「凋落」 are written/formal; 「下がり」 mostly serves as a compound element, as in 「値下がり」; 「上り坂」 is the antonym.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 下くだりとなっている坂道さかみち。
2. 勢いきおいなどが衰おとろえること。