malady:  a sickness or illness; bad health

 

malefactor:  a person who does the wrong thing; an evil person

 

malevolent:  wishing evil or bad will for others; mean

 

malfeasance:  bad conduct or wrongdoing by a public official

 

malfunction:  to function imperfectly or badly; fail to operate normally

 

malice:  a desire to do something bad to someone else; doing something that is wrong on purpose

 

malignant:  very bad or harmful; likely to cause death

 

malnutrition:  a poor diet; bad eating habits that result in poor health

 

malodorous:  stinky, having a bad smell

 

malpractice:  an instance of bad conduct or treatment from a doctor or other professional