Is there a term for not identifying with your current age?

"Transgender" refers to someone who doesn't identify with their birth gender. "Transracial" refers to someone who doesn't identify with their birth race.

Is there a term for someone who doesn't identify with their current age? For example, if someone is 50 years old, but feels a like they are 30?

Perhaps something like "Transaged"? Is there a generally accepted term for this?

Solution 1:

No, Mature for their age and Young at heart are about the best you'll get.

Solution 2:

maybe age dysphoria

Typical Presentation: 1. An enduring concept of self that is younger than one’s chronological age. 2. Intense dissatisfaction with adult characteristics 3. Persistent fantasies of being younger 4. Persistent role-playing (regression) as being younger than one’s chronological age.