an era; an age; a generation

It drew strength from the young people who rejected the myth of their generation's apathy, who left their homes and their families for jobs that offered little pay and less sleep.

Emperor Qin Shi Huang and Emperor Wu of Han, though remarkable in their achievements, somewhat lacked in literary grace; Emperor Taizong of Tang and Emperor Taizu of Song, though commendable in their elegance, still fall slightly short in their brilliance. The proud conqueror, Genghis Khan, knew only how to bend the bow and shoot great eagles. All of them are now bygone, and if you want to count the truly remarkable figures, look to the present age.

It is said that the younger generation today is apathetic.

My faith in the next generation is increasing.

These old customs have been handed down from generation to generation.