Green’s Dictionary of Slang

Cosmopolitan magazine, launched for family audience in 1886, relaunched as women’s magazine in 1965.

1968		P. Roth ‘Civilization and Its Discontents’ in New Amer. Rev. 3 40: ‘Do you know what I read in Cosmopolitan?’ says my mother to my father [...] ‘I’m not making it up. I read it in Cosmo! I’ll show you the article!’.
1986		‘Richard Stevenson’ Ice Blues 92: [L]ying by the pool with the latest Cosmo.