1. in a manner relating to or occurring during the daytime; by day
Usage: often used in scientific or technical contexts
2. on a daily basis; every day
Usage: formal or technical usage

Examples

• Many flowers open diurnally and close at night.
• The animal is diurnally active, hunting during daylight hours.
• The medication should be taken diurnally for best results.
• Diurnally, the temperature rises significantly in the desert.
• The bird feeds diurnally and roosts at night.