斜面|しゃめんshamen[1]atamadaka (head-high)

1. nounslope; slanting surface; bevel
   岩いわは丘おかの斜面しゃめんを転がり落ころがりおちた。↗

   The rock rolled down the hillside.

• SynonymスロープNeutralA loanword for a ramp, as in 「車いす用スロープ」; used mostly for accessibility facilities and in skiing.
• Synonym傾斜けいしゃNeutralTilt or inclination, as in 「傾斜がきつい」; also used figuratively for a leaning of thought or a tendency.
• Synonym坂さかNeutralA sloping road, as in 「坂を上る」; the most common choice in colloquial speech.
• Synonym傾斜面けいしゃめんNeutralAn inclined surface; mostly used in physics and math explanations.
• Related勾配こうばいNeutralNames the degree of inclination, as in 「急な勾配」; it stresses how steep something is, not the slope itself.
• Antonym平面へいめんNeutralA flat surface; a slope can itself be a plane, so to stress that a surface is not tilted say 「水平面」, which contrasts with 「斜面」.

For sloping ground or a slanting surface use 「斜面」, as in 「山の斜面」「斜面を滑る」. Road slopes are 「坂」, steepness is 「勾配」, and accessibility or ski ramps are 「スロープ」. For a surface that is not tilted, say 「水平面」.

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

1. かたむいている地面じめん。
2. 水平面すいへいめんに対たいしてかたむいている平面へいめん。