Definitions

1. noun

A period of 24 hours; a day.

“The diel rhythm of the animals was disrupted due to the artificial lighting.”

2. noun

A cycle of 24 hours in terms of biological processes, especially in relation to circadian rhythms.

“The researcher studied the diel patterns of the nocturnal species.”

3. adjective

Relating to the cycle of 24 hours.

“The diel activity of the marine animals was observed in the laboratory.”