 FTM and MTF are abbreviations of female-to-male and male-to-female. They were originally connected to transsexual (medical) discourse indicating individuals who transition to the “opposite” sex. They are now used in ways that have broken from this medical discourse and may be used more generally to indicate folk who move away from being assigned male (or female) at birth to the “other” direction. They may also be used as primitive (undefined) terms. This means that they are not treated as abbreviations indicating transition from one sex to another. Instead, they are used to simply categorize individuals in a way analogous to the categories man and woman.