nighttime

名词 nighttime:

1. the time after sunset and before sunrise while it is dark outside
   同义词：night, dark

night.time

n.（名词）
The time between sunset and sunrise.
夜间：指从日落到日出的一段时间
adj.（形容词）
Occurring in or appropriate for use during the night:
夜间发生的：发生在夜晚的或适用于夜晚的：
例句：
nighttime activities; nighttime attire.
夜间活动；夜间服装