In the United States, afternoon is generally the time between noon and 5:00 p.m., and evening is considered anything after 5:00 p.m. There is no set allocation for afternoon and evening, however. The determination of the two is largely lifestyle driven, and the concepts of the two may vary slightly around the globe but is generally regarded to correspond with the end of the workday and the time at which dinner is traditionally eaten.
The dictionary definition of afternoon is simply the hours between noon and evening. In the United States, the typical workday ends at 5:00 p.m. This time is, therefore, the generally accepted time for the beginning of evening and is even commonly expressed in English vernacular through the expression, '5:00 o'clock in the evening' as a way of establishing it from its morning counterpart.
For some, evening begins just before the sun begins to set, which is between 6:00 p.m. and 7:00 p.m. Still, for others, evening does not officially begin until sunset. In such places, 5:00 p.m. is still considered late afternoon.
In England, the distinction between afternoon and evening is usually determined by team times. Afternoon tea is a snack that occurs around 4:00 p.m. High tea, or simply "tea" to some, is a hearty meal that sometimes subs for supper.