"Blend of Maria and Luisa"
The name Marialuisa is commonly a female name from the "Italian" origin.
Marialuisa joins the given names Maria and Luisa into one written word. The pairing Maria Luisa is a long-established compound in Italy, Spain and Portugal, and the closed-up spelling follows the Italian practice of writing such pairs as a single name, as in Mariangela and Mariateresa. Both elements are the standard forms of the same two names in those languages.
The pronunciation of Marialuisa is mah-ree-ah-loo-EE-sah.