Black rats, that means bad luck. Black cats, ditto. Bad Omens could also be, like, some people consider shooting stars bad omens, some people consider blondes bad omens, (not a lot of people, though), but it's a form of opinion, some people don't even believe in omens.
We were planning for a picnic, but the dark clouds seemed like a bad omen.
bad omens yet to come
Good omens that people believe in include seeing a shooting star, finding a four-leaf clover, or hearing a bird sing outside your window. Bad omens may include breaking a mirror, seeing a black cat cross your path, or hearing an owl hoot at night.
Good omens were signs of positive outcomes for future actions. The Romans practiced augury, which was a religious cult of reading the omens of the gods. Bad omens signalled that the gods did not approve of the future action. There were many techniques for reading the omens of the gods and there were all sorts of signs.
No. The very concept of "bad omen" is unscientific.
Owls, Crows, and Rats are often considered bad omens, some people believe that wolves are bad luck as well. A good omen would be a dove.
Calpurnia's dream, the soothsayer's prophecy, the bad weather.
Some sailors believe or had believed that pigs or swine were bad omens for sailing.
Full of omens or portents; something which suggests that something bad is soon to happen.
No there has been no bad omens from flinging sparrows.
Because of her nightmare, the bad omens and the augerers results
No, that is just a superstition. Black crickets are just as lucky as any other organism.