Common Words
* maladjusted: poorly adjusted to the environment or society
* malady: a disease or ailment
* malcontent: a person who is habitually dissatisfied
* malfeasance: wrongdoing, especially by a public official
* malformed: badly formed or shaped
* malicious: intending or showing a wish to do evil to others
* malnutrition: a lack of proper nutrition
* malpractice: improper, illegal, or negligent professional activity
* maltreat: to treat badly or cruelly
* malware: software designed to damage or disable a computer system
Less Common Words
* malaise: a general feeling of discomfort, illness, or uneasiness
* malapropos: inappropriate or untimely
* malapropism: the mistaken use of a word for a similar-sounding one
* malarkey: nonsense or foolish talk
* malcontent: a person who is habitually dissatisfied
* malevolent: wishing evil or harm to others
* malformation: an abnormal formation or shape
* malinger: to pretend to be ill in order to avoid work or duty
* malodorous: having an unpleasant smell
* malpractice: improper, illegal, or negligent professional activity
* maltreat: to treat badly or cruelly
* malversation: dishonest or fraudulent conduct by a person in a position of trust
* maladjusted: poorly adjusted to the environment or society
* malapropos: inappropriate or untimely
* malcontent: a person who is habitually dissatisfied
* malediction: a curse
* malefactor: a person who commits a crime
* malevolent: wishing evil or harm to others
* malfeasance: wrongdoing, especially by a public official
* malformation: an abnormal formation or shape
* malinger: to pretend to be ill in order to avoid work or duty
* malodorous: having an unpleasant smell
* malpractice: improper, illegal, or negligent professional activity
* maltreat: to treat badly or cruelly
* malversation: dishonest or fraudulent conduct by a person in a position of trust
This list is not exhaustive, but it provides a good starting point for understanding the various meanings of the prefix "mal-".