What characteristic is associated with something that is diurnal?

The term "diurnal" refers to a pattern or behavior that occurs during the daytime or daily. In biological contexts, it is often used to describe animals that are active during the day as opposed to those that are nocturnal, which are active at night. Hence, the characteristic of occurring every day aligns perfectly with this definition, emphasizing a routine or consistent behavior that takes place within the course of a day. This understanding highlights the importance of recognizing daily activities or cycles, which is fundamental in various fields such as ecology and biology.