In mountaineering in the United States, a thirteener (abbreviated 13er) is a mountain that exceeds 13,000 feet (3,962.4 m) above mean sea level, similar to the more familiar "fourteeners," which exceed 14,000 feet (4,267.2 m).

Why are they called Thirteeners?

He'd heard his generation called “Twentysomethings,” “Thirteeners” (because they're the thirteenth generation since the Declaration of Independence), “Post-Boomers,” and “Baby-Busters.” He didn't like any of those titles.

What is the Thirteeners generation?

In 1992, The Atlantic tried coining “Thirteeners” as an alternate term for Generation X. ... America's thirteenth generation, born from 1961 to 1981, ranging in age from eleven to thirty-one. Demographers call them Baby Busters, a name that deserves a prompt and final burial.