Private is a level of privacy that that exceeds personal but does not reach the level of secret. Private data includes things like your private conversations with your friends and family as well as things like phone numbers, home addresses, and such. Private data should never be accessible to anyone publicly and only to those you trust privately.
One of the greatest mistakes we make is trusting Facebook, Google and others with our private data, which they have demonstrated over and over again is not private at all but that they frequently sell or give to whomever they want without our explicit consent. Removing the names of the data owners does not give them the right to treat our private data as personal or even public.