Deer are crepuscular

[Freeguy]

Bats are nocturnal. They hunt at night. Deer are crepuscular. They are active at dawn and dusk. Cheetahs are diurnal . They hunt during the day.

I searched for the meaning of "crepuscular". No result in Longman was found. However, in the other dictionaries it seems that it means : twilight.
My question is what's the relation among nocturnal, crepuscular and diurnal. I didn't find anywhere such a combination : crepuscular animals!

 

[Amigos4]

Bats are nocturnal. They hunt at night. Deer are crepuscular. They are active at dawn and dusk. Cheetahs are diurnal . They hunt during the day.

I searched for the meaning of "crepuscular". No result in Longman was found. However, in the other dictionaries it seems that it means : twilight.
My question is what's the relation among nocturnal, crepuscular and diurnal. I didn't find anywhere such a combination : crepuscular animals!

Take a look at Crepuscular - Wikipedia, the free encyclopedia and List of nocturnal animals - Wikipedia, the free encyclopedia

 

[MikeNewYork]

Bats are nocturnal. They hunt at night. Deer are crepuscular. They are active at dawn and dusk. Cheetahs are diurnal . They hunt during the day.

I searched for the meaning of "crepuscular". No result in Longman was found. However, in the other dictionaries it seems that it means : twilight.
My question is what's the relation among nocturnal, crepuscular and diurnal. I didn't find anywhere such a combination : crepuscular animals!

And here is a source for diurnal: Diurnality - Wikipedia, the free encyclopedia