What is a “crypto-portrait”?

I have frequently seen the word crypto-portrait popping up in articles on Wikipedia and elsewhere, but I was not able to find a definition for it. Apparently there used to be an article on Wikipedia but it has since been removed (there are dead links to it).

Here are some of the places you can see the word used:

  • http://thelostdutchman.hubpages.com/hub/The-Van-Eyck-Cryptogram
  • http://www.discoverbaroqueart.org/database_item.php?id=monument;BAR;cz;Mon11_F;7;en
  • http://www.desipientia.nl/archief.php?nummer=41

Solution 1:

Crypto-portrait is an art history term for a portrait of a person which is not identified as such. For example, the painting below is Dance of Salome, 1452–1457, by Fra Filippo Lippi. Some art historians suspect this “Salome” is a crypto-portrait: a likeness of Lippi’s mother.

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