SchismFrom the Latin scindere, cut.  Division or separation, specifically in religious issues. Formal separation within or from an existing religion, on account of some difference of opinion with regard to matters of doctrine, or discipline.   The offense of seeking to produce a division in a religion.   
SchismaticFrom the Latin schismaticussplit, schism.  Pertaining to schism. Of the nature of schism.  Characterized by schism, as schismatic opinions; a schismatic tendency.  One who separates from an existing religion on account of a difference in opinion; one who partakes in a schism. Schismatical – tainted with schism; schismatic.