fiend

UK: fiːnd | US: fiːnd

Definition
  1. n. an evil spirit or demon

  2. n. a person who is extremely cruel, wicked, or obsessed with something (e.g., "a fitness fiend")

Structure
fien <hostile>d <old English noun suffix>
Etymology

The word "fiend" traces back to Old English fēond, meaning "enemy" or "devil," derived from Proto-Germanic fijandz ("hating, hostile"). The root fien- is linked to the verb fēogan ("to hate"), reflecting its original sense of a hostile adversary. Over time, it narrowed to specifically denote supernatural evil (demons) and later metaphorically for humans exhibiting extreme malice or obsession. The "-d" suffix is an Old English nominal ending, now fossilized in modern spelling.

Examples
  1. The legend spoke of a fiend lurking in the abandoned castle.

  2. He transformed into a fiend when provoked, terrifying everyone around him.

  3. She’s a coffee fiend, drinking at least five cups a day.

  4. The villain in the story was a true fiend, devoid of compassion.

  5. Medieval art often depicted fiends tormenting sinners in hell.