Some know “sigma” as the 18th letter of the Greek alphabet but it’s also teen slang for a cool dude. According to Know Your Meme, sigma is “referring to a supposed classification for men who are ...

Beth Skwarecki is Lifehacker’s Senior Health Editor, and holds certifications as a personal trainer and weightlifting coach. She has been writing about health for over 10 years. A bullshit concept ...

Alpha males have competition. These men, who don't see beyond their navel and who stick to this image of raw virility, have slightly lost ground. Sigma men, a sort of "lone wolf" on the fringes of the ...