noun, noun or participle which takes 'suru', intransitive verb
setting out at night; departing at night
Refers to the act of starting a journey or leaving during the night. Can be used as a noun or as a suru-verb (夜立ちする).
旅人は夜立ちして、朝までに次の町へ着いた。
The traveler set out at night and reached the next town by morning.
夜立ちは危
Setting out at night is dangerous, so let's leave after it gets light.
noun
nighttime penile erection; nocturnal erection
Medical/physiological term. Often contrasted with 朝立ち (morning erection). Used as a noun; not commonly used as a suru-verb.
See also: 朝立ち
夜立ちは健康な男性に自然に起こる現象だ。
Nighttime erections are a natural phenomenon in healthy men.
医者は夜立ちの有無を診断の参考にすることがある。
Doctors sometimes use the presence or absence of nocturnal erections as a diagnostic reference.