Spanish:
* Mendoza: A very common Spanish surname, meaning "mountain."
* Martinez: Meaning "son of Martin."
* Marquez: A common surname, meaning "marker" or "boundary."
* Miranda: Meaning "to look, to admire."
* Moreno: Meaning "dark complexion."
* Morales: Meaning "customs, manners."
* Molina: Meaning "mill."
* Mendez: Meaning "son of Menendez."
* Madrid: From the city of Madrid, Spain.
* Manzanarez: Meaning "apple tree."
* Macias: An ancient Spanish surname.
* Malave: A surname of Basque origin.
Mexican:
* Mendez: Same as above.
* Martinez: Same as above.
* Mejia: Meaning "son of Miguel."
* Molina: Same as above.
* Monterrey: From the city of Monterrey, Mexico.
* Maya: A surname of indigenous Mexican origin.
Other Hispanic:
* Marquez: Same as above.
* Miranda: Same as above.
* Moreno: Same as above.
* Mendez: Same as above.
* Molina: Same as above.
* Macias: Same as above.
This is just a small sampling of the many Hispanic last names starting with "M". Remember that the specific meaning and origin of a surname can vary depending on the region and individual family history.