psychopathic

From psycho- +‎ -pathic.

• (US) IPA^(key): /ˈsaɪkoʊˌpæθɪk/, /ˈsaɪkəˈpæθɪk/

psychopathic (comparative more psychopathic, superlative most psychopathic)

1. Exhibiting the behaviors and personality traits of a psychopath.

   A psychopathic killer is on the loose.

   • 1902, William James, “Lecture I”, in The Varieties of Religious Experience […] ‎, London: Longmans, Green & Co.:

     [T]he psychopathic temperament, whatever be the intellect with which it finds itself paired, often brings with it ardor and excitability of character.

• psychopathologic, psychopathological (as explained there)

psychopathic (plural psychopathics)

1. (dated) A psychopath.