fanatical
Americanadjective
adjective
Usage
What does fanatical mean? Fanatical means having and being motivated by an extreme and often unquestioning enthusiasm, devotion, or zeal for something, such as a religion, political stance, or cause. A person who shows such extreme enthusiasm or devotion is called a fanatic. Sometimes, fanatic is used negatively to imply that someone takes such devotion too far, as in They’re considered religious fanatics due to their extreme practices. Close synonyms are extremist, radical, and zealot. Other times, fanatic is not used negatively but instead simply refers to someone who is extreme in their devotion or enthusiasm for an interest or hobby. For example, calling someone a sports fanatic means they’re an extremely enthusiastic fan of sports. In fact, the word fan is a shortening of fanatic. Fanatical can be used to describe either a kind of fanatic or such a person’s beliefs or behavior. Example: We dismiss these extreme beliefs by calling them fanatical, but they may be more widespread than we think.
Related Words
See intolerant, radical.
Other Word Forms
Etymology
Origin of fanatical
Explanation
If you are excessively enthusiastic about something — a sports team, an actor, your religion, saving the whales, a certain brand of chocolate — then you are fanatical about it. Fanatical comes from the word fanatic, which itself came from the Latin fanaticus, meaning "mad" or "inspired by a deity." The root word is fanum, or "temple." The original English meanings of both fanatic and fanatical implied that the person being described was insane with enthusiasm, like a religious zealot. The word fan is likely shortened from fanatic, and thus shares the same roots, but that word doesn't imply the same obsessiveness that fanatical does.
Vocabulary lists containing fanatical
"To Kill a Mockingbird" by Harper Lee, Chapters 7–11
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
The Bean Trees
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
"Simon's Saga," Vocabulary from Episode 34
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
But during the greatest turnaround that Silicon Valley has ever seen, Jobs was fanatical about one idea: Apple was a place to invent the future, not dwell on the past.
From The Wall Street Journal • Apr. 3, 2026
To all but his most fanatical followers, it’s clear he possesses a megalomaniacal personality and violent temperament.
From Salon • Mar. 7, 2026
India captain Suryakumar Yadav admitted Friday "there will be nerves" when India open their T20 World Cup campaign in front of more than 30,000 fanatical home supporters in Mumbai, but vowed to give them "entertainment".
From Barron's • Feb. 6, 2026
Superstar players, fanatical fans, regular helpings of drama and the sinister side of the game - the Superclasico has it all.
From BBC • Apr. 27, 2025
I had also become a fanatical bird-watcher by the age of seven.
From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond
![]()
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.