to knit (one's eyebrows); to furrow; to contract
「顰める」 has another reading with different meanings.
to screw up (one's face); to scrunch up; to pucker up; to furrow (one's brow); …
to knit one's brows (in discomfort, unease, disapproval, etc.); to raise one's …
彼は眉を顰めた。
He knitted his eyebrows.
なぜそんなに眉を顰めるのか。
Why do you knit your eyebrows so much?
彼女は心配そうに眉を顰めていた。
She was knitting her eyebrows worriedly.