Used for economic or market trends, such as a recovery in the economy, rising prices, or an upward turn in business conditions.
The economy has finally turned upward.
物価のアップターンが続いている。
The upturn in prices continues.
In skiing, refers to the upward curve at the tip of a ski.
スキーのアップターンが雪に引っかからないように注意する。
Be careful so the ski's upturn doesn't catch on the snow.