The Italian word “Mona” in the title Mona Lisa means “my lady.” More precisely, the traditional Italian spelling is “Monna,” a contracted form of “madonna,” derived from “ma donna,” meaning “my lady.”
It was a polite form of address comparable to “Madam” or “ma’am,” rather than the woman’s personal name. The title assumes that Leonardo’s sitter was Lisa Gherardini, the wife of Florentine merchant Francesco del Giocondo.
The painting is also called La Gioconda in Italian. That name refers to Lisa’s married surname and can suggest “the joyful” or “jovial one,” creating a second layer of meaning. A common mix-up is treating “Mona” as a separate first name or translating it simply as “Madame”; “my lady” is the closest literal equivalent.