say it: feend
fiend is a noun meaning "a cruel wicked and inhuman person". It carries 3 recorded senses.
a person motivated by irrational enthusiasm (as for a cause)
“A fanatic is one who can't change his mind and won't change the subject”
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for fiend come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.