1. verb To make a change to one's external gender presentation to align with one's internal gender identity. The process of transitioning can include many different actions, either individually or in combination, such as changing one's name or undergoing medical intervention, such as sex reassignment surgery or hormone replacement therapy. She plans to transition by doing hormone replacement therapy.

2. noun The process of making such a change. The hardest part of my transition was not having the full support of some of my friends, unfortunately.