To knit or furrow (one's brows); to contract one's face to show displeasure, doubt, or discomfort (commonly used in expressions like 眉をひそめる).
彼はその説明を聞いて眉をひそめた。
He furrowed his brows when he heard that explanation.
寒さで目をひそめて歩いた。
I squinted/wrinkled my face and walked because of the cold.
その冗談に母は思わず顔をひそめた。
At that joke, my mother couldn't help but frown.