malfeasance n[mal- bad + obsolete English feasance doing, execution, from Old French faisance , from fais- , stem of faire to make, do, from Latin facere ]
: the commission (as by a public official) of a wrongful or unlawful act involving or affecting the performance of one's duties compare misfeasance , nonfeasance
Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.