diurnal

Từ điển WordNet v3.1 - WordNet Dictionary

adjective

1. of or belonging to or active during the day
- diurnal animals are active during the day
- diurnal flowers are open during the day and closed at night
- diurnal and nocturnal offices
• Ant:
nocturnal
• Topics:
biology, biological science
2. having a daily cycle or occurring every day
- diurnal rotation of the heavens
• Similar to:
periodic, periodical