verb · to come and go or roam about, often while remaining mostly unseen

这一带海域经常有海盗出没。

verb · to haunt a place as a ghost or to stalk a location as a criminal

传说深夜常有鬼魂在废墟中出没。

verb · to rise and set, referring specifically to the movements of the sun, moon, or stars

太阳的出没规律随季节而变化。