misbehave:  to act our badly or in the wrong way

 

mischievous:  tending to make minor bad choices; teasing; full of tricks; naughty

 

miserable:  feeling badly; the condition of feeling unhappy

 

misfortune:  bad luck

 

misjudge:  to make a wrong or unfair decision about someone

 

mislead:  to guide someone into the wrong direction; to be a bad influence

 

misspell:  to spell a word the wrong way

 

mistake:  a bad or wrong decision; error

 

mistreat:  to treat someone badly

 

misunderstand:  to think the wrong thing about what was communicated