nocturnal
adj. （动物）夜间活动的；夜间发生的
例句
The dormouse is a shy, nocturnal creature.
榛睡鼠是一种在夜间活动的胆小动物。
《牛津词典》
Nocturnal animals sleep by day and hunt by night.
夜间活动的动物白天睡觉晚上猎食。
When there is a full moon, this nocturnal rodent is careful to stay in its burrow.
在有满月出现的时候，这种夜间出没的啮齿类动物小心地呆在它的洞里。
《柯林斯英汉双解大词典》
