One's line of sight; gaze. Refers to the direction and focus of where someone is looking, often used in expressions like 'to catch someone's eye' or 'to avert one's gaze.'
彼女の視線がテーブルの上の指輪に向いた。
Her gaze turned to the ring on the table.
講演中、会場の視線を集めるのは難しい。
During a lecture, it's hard to capture the audience's attention.
彼は視線をそらして、その質問には答えなかった。
He looked away and did not answer that question.