flagitious
Concise Oxford English Dictionary © 2008 Oxford University Press:
flagitious /fləˈdʒɪʃəs/
▶adjective formal extremely and criminally wicked.
– derivatives
flagitiously adverb,
flagitiousness noun.
flagitiously adverb,
flagitiousness noun.
– origin ME: from L. flagitiosus, from flagitium ‘importunity, shameful crime’, from flagitare ‘demand earnestly’.
'flagitious' also found in these Oxford entries:

