Elon Musk tweeted on Wednesday that the words “cis” and “cisgender” are now considered slurs on Twitter. The CEO and billionaire tweeted the announcement shortly after midnight ET on Wednesday in response to a user who claimed to have been harassed by trans rights activists. James Esses tweeted on Tuesday saying he ‘rejected’ the word ‘cis’ and received “a slew of messages from trans activists calling me ‘cissy’ and telling me that I am ‘cis’ ‘whether or not I like it.’” Cisgender refers to anyone whose gender identity aligns with the sex they were assigned at birth. Sign up to our free Indy100 weekly newsletter Despite the claims from many anti-trans activists that the term cisgender is relatively new, the Oxford English Dictionary notes that the term became popular back in the 1990s. This isn’t the first time the billionaire has promoted anti-trans sentiment. In April, Musk removed Twitter’s previous ban on deadnaming transgender individuals. A move that was denounced by LGBT+ advocacy organisation GLAAD. Some have speculated that much of Musk’s promotion of anti-trans views and rhetoric is related to his estranged daughter, who is trans. Many have criticised Musk’s announcement: Despite Musk’s announcement that ‘cis’ and ‘cisgender’ are now considered slurs, there has been no update to Twitter’s official guidelines. It is also not clear what the consequences are for using such terms. However, many have been quick to point out that Musk’s announcements haven’t always followed through or been implemented. Have your say in our news democracy. Click the upvote icon at the top of the page to help raise this article through the indy100 rankings.