legitimize

1. V-T To legitimize something, especially something bad, means to officially allow it, approve it, or make it seem acceptable. 使(尤其是坏事)合法化; 正式批准(或认可)[正式]

They will accept no agreement that legitimizes the ethnic division of the country. 他们不会接受任何使国家民族分裂合法化的协议。