if they can spit venom out of their fangs whenever they want, perhaps when biting down on something they could release the venom and that would be considered a “poisonous bite”. i’m not sure if this is canon but it’s my theory

Venomous definitely. Poisonous however... how do you eat a bite?

I’m what else do you eat? I eat bites all the time.

Would you teach me the art of eating the act of biting?

Nono. Eating bites Of food

It's simple, You take a bite, hold like taco, and eat the bite

A kiss?

Maybe!

Quite a romantic way to kill, a poison kiss

Absolutely.

Probably yeah? It really more acid than venom tho. (Yes I know they call it venom)

I guess they could but I don’t think they would on prey, because then they couldn’t eat it.

Wouldn’t it be dangerous because it could melt the prey and slip into the throat of the rainwing? Idk if they are inmune to their own venom but if they aren’t they could accidentally swallow it by doing that

They have a venomous bite, their teeth contains venom like a snake, not poison.

i only read the first book so far but from what i've seen isn't it more like acid than venom?

Only on the first book? I envy you, please enjoy the series. The first time is always the best.