To become late or for time (especially night) to advance; to grow late/night deepening.
話し込んでいるうちに、いつの間にか夜が更けていた。
We were talking and before we knew it the night had grown late.
冬も更けて、窓の外は凍えるような寒さだ。
As winter deepens, it's freezing outside the window.
夜更けに帰宅すると、家族はもう寝ていた。
When I got home late at night, the family was already asleep.