Pro tip: If you bite it, it's poisonous. If it bites you, it's venomous.
The phrase you are looking for is "venomous".
I personally imagine at least some carnivorous dinosaurs weren't necessarily venomous in the same way that a handful of modern snakes are, (potentially) save for the fellow in Dark's link. Rather, they had a similar toxicity of horror that Komodo Dragons do in their saliva, perhaps bolted up to nightmare levels.
Though there probably isn't any evidence for it, I'd figure that there might be enough rot in a carnivore's level to at least cause an infection in those who survived a bite...which happens a lot more frequently than we typically account for. Remember, just because it's an apex predator in its prime, that doesn't mean it's going to make a kill every time. It's going to fail so much more than it succeeds, like every modern predator.