[Facts] Re: Japanese name...
The meaning depends on the kanji (characters) the parents chose to write the name with. If you know one particular person named Misa you could find out what her name means, but it's not possible to generalize as Misa has dozens of potential "meanings." The first character (Mi) could mean beauty, three, heart, fruit, and more, and the second (Sa) could be bloom, early, gauze, cherry, and more.