noun, noun or participle which takes 'suru', intransitive verb
undulation; waviness
Describes the rise and fall of land, waves, or a surface; often used in geography and landscape descriptions.
この地域は地形の起伏が激しい。
This area has dramatic undulations in the terrain.
丘陵地帯が緩やかに
The hilly area undulates gently.
noun, noun or participle which takes 'suru', intransitive verb
ups and downs; highs and lows
Figurative use for emotional, economic, or life fluctuations; often paired with words like 感情, 人生, or 景気.
人生には起伏がつきものだ。
Life is full of ups and downs.
彼の感情は激しく起伏する。
His emotions fluctuate wildly.