pinxit

from The Collaborative International Dictionary of English v.0.48

Pinxit \Pinx"it\ [L., perfect indicative 3d sing. of pingere to
   paint.]
   A word appended to the artist's name or initials on a
   painting, or engraved copy of a painting; as, Rubens pinxit,
   Rubens painted (this).
   [1913 Webster]