The describing word that goes with sociopath: showing the behaviour of someone who has no conscience about other people — lying, using people, feeling nothing when they are hurt, possibly dangerous. It usually describes behaviour, tendencies, or a person's manner rather than being a label pinned on a person: 'sociopathic behaviour', 'a sociopathic disregard for other people', 'sociopathic charm'. It also gets stretched in journalism and business talk to describe organisations, not just people — 'a sociopathic company that treats workers as numbers' — meaning it acts without conscience. Like sociopath, this is popular language rather than medical language; doctors would write 'antisocial personality disorder'. As an adjective it is a shade less accusing than the noun, because you can criticise an act ('that was sociopathic') without declaring what someone permanently is — but it is still strong.