transkid

From trans- +‎ kid.

transkid (plural transkids)

1. (informal) A transgender child.
   • 2012, Rachel Pepper, Transitions of the Heart:

     The more I learned about transkids, the more I grilled you, every day. I'm ashamed of my relentlessness, but I had to know.
     “Why do you want to be a boy?”
     “I don't know.”

• stinkard