A Ginger Prince is a phrase commonly used to describe a friend in social circles who has ginger hair but however is not a Prince. The irony in the phrase comes from the recipient of said phrase being not of royal extract but definitely being Ginger.

The origins of the phrase come from the UK. Prince Harry of Windsor is the second son to Prince Charles, the Prince of Wales and the late Princess Diana. Prince Harry unlike his brother has Ginger Hair and has been known by the media and press as the ‘Ginger Prince’.

The common use of the phrase ‘Ginger Prince’ used to describe a friend who has Ginger Hair caught on in the UK after this use by the press of the term. The phrase is now common across the UK and is deemed more affectionate and ironic than derogatory.
Reference:

Person 1: Where’s Micky T?
Person 2: Who? You mean the Ginger Prince?! He’ll be here for Lasties fella.

(Common context of the use of the phrase)
by Jack Roseby April 12, 2008
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The ginger Prince. the name for some one with the ginger affliction. Usually used in public gatherings when you have to be polite, or when you want something off the ginger cunt
Hey the ginger prince has arrived, don't suppose you can borrow me a tenner.
by thegingerprince March 12, 2008
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