The definition of a fiend is someone who obsesses over an activity or thing.(noun)
A fiend is defined as a person who is evil and cruel.(noun)
An example of a fiend is someone who is not kind to animals.
See fiend in Webster's New World College Dictionary
Origin: ME fend, feend < OE feond, lit., the one hating, orig. prp. < base of feogan, to hate, akin to Goth fijands < fijan, to hate < IE base *pē(i)-, to harm
See fiend in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English fēond; see pē(i)- in Indo-European roots.
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