expression, ichidan verb
smile; raise the corners of one's mouth
Describes the physical action of lifting the corners of the mouth, often used in instructions for facial exercises, acting, or describing a deliberate smile.
写真を撮るときは、口角を上げると自然な笑顔になります。
When taking a photo, raising the corners of your mouth gives a natural smile.
彼女は口角を上げて、にっこりと笑った。
She raised the corners of her mouth and smiled brightly.