noun
vertical furrow between the eyebrows
Refers specifically to the vertical wrinkle or crease that appears between the eyebrows, often from frowning or aging.
彼は怒ると眉間に深い縦ジワができる。
When he gets angry, a deep vertical furrow forms between his eyebrows.
最近、縦ジワが気になってきた。
Lately, I've become concerned about the vertical lines between my eyebrows.
Compound of 縦 (たて, 'vertical') and 皺 (しわ, 'wrinkle'), with the latter often written in katakana as ジワ for clarity or stylistic reasons.