Using Lexipedia you can visually map out words and concepts in a clean and friendly interface. No more thumbing through a dictionary, or fumbling through a single-word search; with Lexipedia you can see related words, synonyms, antonyms and fuzzynyms. And best of all, it's absolutely free!
n.
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"--Winston Churchill
n.
a member of an ancient Jewish sect in Judea in the first century who fought to the death against the Romans and who killed or persecuted Jews who collaborated with the Romans