Retransition 

Someone who previously underwent a gender transition, later detransitioned, and then transitioned again.

Detrans Friend: Hey, I thought you detransitioned, but I noticed you started going by a male name again.

Retrans Friend: Oh, yeah. Sorry, I forgot to mention it. Transitioning is the right thing for me right now, so I'm retransitioning. I'm glad I went through the experience of detransitioning though. It really clarified my understanding of my gender identity.

Detrans Friend: I'm happy for you! I know who to talk to if I ever decide to retransition in the future.

Trans Friend: Doing the paperwork for one name and gender change and going through one medical transition was hard. I don't know how y'all do it.

Retrans Friend: I'm never gonna financially recover from this.

Retransition by simoncow January 5, 2022

detransitioner

Noun, for someone who is detransitioning, ie halting or undoing gender transition. A detransitioner might or might not continue to identify as a member of the trans "umbrella".

I'm a detransitioner and proud.

detransitioner by jouissancepastance June 9, 2016

detransition

To halt or undo gender transition. During and after detransition, one might or might not continue to identify as a member of the trans umbrella.

Detransition is more difficult than transition, but it's worth it.

detransition by jouissancepastance July 26, 2018

Political Detransitioner

A person who has detransitioned and now takes part in advocating for anti-transgender legislation (typically gender-affirming care restrictions) or against transgender movements and rights. Sometimes this is strictly for political reasonings or revulsion against gender-affirming care providers or transgender people.

A political detransitioner came to testify in support of an anti-gender-affirming care bill.

Political Detransitioner by BLKTRNSLIVESMTTR April 16, 2023