Pronunciation: (fēnd),[key] —n. 1. Satan; the devil.
2. any evil spirit; demon.
3. a diabolically cruel or wicked person.
4. a person or thing that causes mischief or annoyance: Those children are little fiends. 5. Informal.a person who is extremely addicted to some pernicious habit: an opium fiend. 6. Informal.a person who is excessively interested in some game, sport, etc.; fan; buff: a bridge fiend. 7. a person who is highly skilled or gifted in something: a fiend at languages.