Harry Potter” author J.K. Rowling has faced sharp criticism for recent tweets about gender and sex, which some have deemed transphobic.

Rowling, who has come under fire from the trans community before, tweeted disparagingly about an article with the headline that included the phrase, “people who menstruate.”

After sparking the uproar, Rowling tweeted:

“If sex isn’t real, there’s no same-sex attraction. If sex isn’t real, the lived reality of women globally is erased. I know and love trans people, but erasing the concept of sex removes the ability of many to meaningfully discuss their lives.”

In one tweet, Rowling referenced the term “TERF,” suggesting that she has been called a TERF and saying “Times change. Woman-hate is eternal.”

TERF is an acronym that stands for trans exclusionary radical feminists. The term describes feminists who are transphobic.

Is TERF an insult?

While some people who are called a TERF say the word is derogatory, LGBTQ advocates say those who hold such views deny transgender people their full humanity and go against what the medical community today has accepted as scientific fact around gender and sex.