Doomer is a 21st-century neologism for an online subculture of men who share extremely pessimistic, nihilist or fatalistic views about global problems such as overpopulation, peak oil, climate change, ecological overshoot, pollution, nuclear weapons, democratic backsliding, economic collapse, and runaway artificial intelligence. Some doomers believe these problems may lead to societal collapse, or even worse, human extinction. The terms doomer and doomerism arose primarily on social media and later experienced a semantic change, becoming Internet slang for pessimism while overlapping with the incel subculture and blackpill.