Of, relating to, or having the nature of an anathema; deserving curse or excommunication.
From anathema plus -ical (relating to), a more formal extension of anathematic. Emphasizes the curse or condemnation aspects.
The -ical ending makes it sound extra archaic and biblical—if you read 'anathematical' in a 17th-century text, you're probably reading about religious condemnation pronounced with maximum gravity.
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