How to say "nighttime" in Japanese

• 夜間やかんJLPT N2approx.Common
  noun, adverbThe common noun for the nighttime hours treated as a period of time, as in schedules, signs, and announcements about when something operates at night.
  フクロウは昼間ひるま寝ねていて夜間やかん狩かりをします。↗

  An owl sleeps by day and hunts by night.
• 夜分やぶん
  noun, adverbLess common; a polite term covering the evening and night, heard chiefly in apologetic phrases when phoning or writing to someone late — rarely the neutral word for 'nighttime' itself.

For 'nighttime' as a plain period of the night, 夜間 is the usual choice; 夜分 is a less common, polite term used mainly to apologize for disturbing someone late at night.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 夜間やかんnight
• 夜分やぶんevening