fiendish Get Printable Handwriting (fiend-ish) 2 syllables Rhymes Learn It! Spelling Test Definition adjective. of or relating to or worthy of an evil spirit Example Sentence He took a fiendish delight in playing mean tricks. Synonyms demonic; devilish; satanic Antonyms angelic Rhymes Two Syllable Rhymes (1) fiendish Share with your friends: