Basically someone who has no empathy, no conscience, and no fear of God's judgment. Doesn't mean they automatically go around killing other people or scamming them. But they wouldn't feel bad if they did. Prisons are full of dumb sociopaths, politics and country-clubs are full of smart sociopaths.
A sociopath is someone with a personality disorder. This disorder includes extreme antisocial attitudes and also behavior. These individuals exhibit a lack of conscience or have little or no respect for the laws and customs of society.