The unlawful use of a liberty or benefit such as may lead to its forfeiture; †an instance of this (obsolete).
Misuse of a franchise or an office granted by the monarch, esp. when it results in its forfeiture; = misuser, n.2
An illegal or improper act by a professional person or an official, esp. one by which the position or office of the perpetrator is used to his or…
= malpractice, n. 2. Obsolete.