How about "Mushalah"? This is the Arabic name given to one of the stars in the constellation of Scorpio -- specifically, a star forming the stinger in the Scorpion's tail. The name means "raised" and refers to the position of the sting ready to strike. The star was named by the 11th century Arabic astronomical writer, Al Biruni.
If you'd like to give me your zodiac sign, I can look up an Arabic name for one of stars in your own particular sign. It may not begin with the letter "M", but it'll have more personal significance, if that's what you're looking for. I'm using a wonderful reference resource titled: *Star Names: Their Lore and Meaning* by Richard Hincley Allen.
-- Nanaea