Loads of dumbasses in this thread.
Evening is the time after work ends, and before you go to sleep.
No. It was a trick question and you all fell for it.
Evening starts when the average person in the world eats dinner. It is based on that specific time. So you find out when everyone eats dinner, average the times and that specific time on the clock is when evening starts. This way it is not subject to outliers and anomalies in peoples eating habits nor is it subject to the season. boom.
So not really a trick question. But a hard question.