misfeasance
Concise Oxford English Dictionary © 2008 Oxford University Press:
misfeasance /mɪsˈfiːz(ə)ns/
▶noun Law a transgression, especially the wrongful exercise of lawful authority.
– origin C17: from OFr. mesfaisance, from mesfaire, from mes- ‘wrongly’ + faire ‘do’; cf. malfeasance.
'misfeasance' also found in these Oxford entries:

