The crossword solution for the term MONA ___ SMILE is 'LISA'. Mona Lisa is a 16th century portrait painted by the Italian artist Leonardo da Vinci. It is one of the most famous paintings in the world and is known for its mysterious smile. The painting is believed to be a portrait of Lisa Gherardini, the wife of Francesco del Giocondo. The painting is currently on display at the Louvre Museum in Paris, France.