from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A prince who rules during the minority, absence, or incapacity of a sovereign.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. a prince who rules a monarchy in the capacity of a regent who is unfit to rule for whatever reason
Sorry, no etymologies found.
Soon after this, the prince regent succeeded to the throne as Dom Joao VI.