|the years separating one generation from the generation that precedes or follows it, esp when regarded as representing the difference in outlook and the lack of understanding between them|
The differences in customs, attitudes, and beliefs between any two generations, but especially between youths and adults.
A broad difference in values and attitudes between one generation and another, especially between parents and their children. For example, There's a real generation gap in their choice of music, restaurants, clothingyou name it. [1960s"