4B movement

4B or "Four Nos" is a radical feminist movement that originated in South Korea. The name refers to its defining four tenets which all start with the Korean-language term bi (Korean: ; Hanja: ), roughly meaning no. Its proponents do not date men, marry men, have sex with men, or have children with men. The movement emerged between 2017 and 2019 on Twitter and on the website WOMAD. It has since spread internationally, namely to the United States after its 2024 presidential election.

The movement is considered fringe in South Korea, and it has since reportedly declined there. In South Korea, a portion of its members, particularly those associated with the apparently misandrist WOMAD, were described as transphobic and homophobic towards gay men.