夜间
yè jiān · HSK 5
nighttime
🌙 夜 = night + 间 = interval/space; literally the night-interval
夜 means night; 间 means a span or gap of time. Together 夜间 marks the stretch of hours during the night — used for things scheduled in that window, like 夜间课 (night classes).
夜 — 亠 lid + 亻 person + 夕 evening moon
夜 originally depicted a person (亻) under a roof (亠) with the moon (夕) beside them, evoking nighttime rest. The moon component 夕 carries the meaning of evening, while the surrounding elements set the scene of a person at night. Over time it came to mean 'night' in general.
间 — gate 門 + sun 日 (originally moon 月)
Originally written 閒, showing the moon 月 shining through a gate 門 — the gap or space between the doors. The moon was later replaced by 日 (sun), giving the modern 间. The core meaning 'space/interval between' extended to time intervals, rooms, and the measure word for buildings.