The rise of patriarchal populist leaders over the past decade has fortified a long-standing campaign by conservative governments and advocacy groups to undermine women’s international human rights. Their efforts have increasingly focused on revising language as a means to challenge and weaken the international norms and organizations essential to women’s and girls’ equality and health. Through our textual analysis of UN records, governmental and nongovernmental publications, media coverage of disputes over language, and background interviews with activists, we identify and delineate the significance of this ‘norm spoiling’ strategy and trace its expansion during the Trump administration. We find that women’s rights challengers have pursued three distinct spoiling tactics based in language: controlling what women’s rights advocates can say through policies such as the United States’ ‘global gag rule’; altering the meaning of women’s rights by reframing them as an attack on other rights, such as religious freedom; and deleting foundational words, such as ‘gender’ and ‘sexual and reproductive health and rights’, from international agreements. The role of language in today’s patriarchal populism goes beyond populist leaders’ speeches, rallies and tweets. Their governments and allies systematically control, alter or delete words central to women’s rights.