1to penetrate; to sink in (to penetrate deeply or have a strong, penetrating effect).
冷たい風が骨まで徹するように感じた。
I felt the cold wind penetrate down to my bones.
彼の言葉は心に深く徹した。
His words sank deeply into my heart.
2to devote oneself to; to be wholly absorbed in (to concentrate or be fully committed to something).
試験対策に徹して、3日間ずっと勉強した。
I devoted myself to exam prep and studied nonstop for three days.
彼は研究に徹して論文を仕上げた。
He concentrated entirely on his research and finished the paper.
チームは勝利に徹して戦った。
The team fought with single-minded devotion to victory.
3to do something throughout a period (e.g., to stay up all night doing something).
会議は夜を徹して行われた。
The meeting went on throughout the night.
イベントの準備で、スタッフは朝まで徹した。
Staff worked through the night preparing for the event.