No, at least not according to what I've heard, and I've never found a way except deleting my entire save file.
Chat with our AI personalities
There is a building next to the POKeMART in Eterna City. Talk to the old man at the table in there and he'll rate your nickname and/or let you name or rename it.
anything you want
You can rename a pokemon by going to the Name rater
The wild yellow hair friend in the game; he's in the introduction of the game.
sorry...i don't think there is one