sigma male /ˈsɪɡmə ˌmeɪl/ noun1 •(Internet, humorous) A self-reliant and assertive male who occupies a position outside a social or group hierarchy; a lone wolf or maverick.I was the timid boy, but now developed in the Sigma Male. Captain of my own tug boat, but soon I'll have that Yacht to Sail. — 2010 formssigma males