While to some the word transgender feels brand new, the term didn’t spring up out of nowhere with, say, Laverne Cox or Transparent. When transgender entered the popular lexicon through the efforts of activists and aid organizations in the mid-1990s, it replaced transsexual, which had replaced transvestite, which was what they called cross-dressers and before that viragos. Transgender was and is regarded as an umbrella category, and in the mid-’90s the two primary terms under that umbrella were female to male (FtM) and male to female (MtF).

These terms captured what were then the major constituencies of transgender identity: those who were born female and lived as men and those who were born male and lived as women. But even at the moment of their emergence into the vernacular, FtM and MtF weren’t sufficient to describe the whole community: They coexisted with terms like third gender, which captured those who didn’t experience gender as incorporating a sense of “to-ness” at all—it wasn’t a journey from one point to another.

The terms FtM and MtF hung on through the early 2000s, but they haven’t fared well in the ’10s. These days, the terms trans-man and trans-woman, or just trans-person, have largely replaced FtM and MtF, with a growing number of folks preferring to use trans-masculine or trans-feminine. From the outside, this could look like another minor semantic disagreement, the infighting of a group often derided for its sensitivity around terminology. But the shift of identity vocabulary within the transgender community merits closer examination: Understanding what the trans community is trying to assert and defend can help everyone—cisgender folks included—comprehend what gender is, where it comes from, and how it operates. These are important lessons in a time where the deadly workings of culturally valorized, indeed “toxic,” masculinity are more evident than ever. Read more via Slate