Misdemeanor – A criminal offense of less severity than a felony. A misdemeanor is a crime that is less serious than a felony, either because the conduct is defined to be a misdemeanor by statute or because the punishment assessed for the conduct is less than that for a felony. Usually, an offense that is not punishable by death or by imprisonment for a year or longer is a misdemeanor. Misdemeanors tend to be crimes in which the nature of the perceived wrongdoing of the offense is less than that of a felony.
Most states distinguish between degrees of misdemeanor, using different language to divide them and assign to each lesser degree a diminished severity of the penalty to be assessed. Some jurisdictions distinguish gross misdemeanors both from misdemeanors and from minor misdemeanors, though minor misdemeanors have at times been treated as a distinct category from other misdemeanors. Some jurisdictions have first-degree through fifth-degree misdemeanors, and some have class A though class D misdemeanors.
Note: the U.S. Constitution specifies that the President may be impeached for “High Crimes and Misdemeanors,” and similar language is found in state constitutions. It seems clear that the term in this setting is used in its sense as misconduct and not as a category of petty offense.
Also see felony