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diehard

[dahy-hahrd] / ˈdaɪ hɑrd /
NOUN
overenthusiastic person
Synonyms
STRONGEST
fanatic fundamentalist zealot
STRONG
bourbon extremist fogy mossback praetorian pullback reactionary right right-winger rightist stick-in-the-mud ultraconservative
WEAK
bitter ender dyed-in-the-wool intransigent old liner standpat standpatter true blue

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 Samsung tempered expectations for the gigantic device, with an executive describing it as a special-edition product for diehard fans rather than for the masses.

From The Wall Street Journal • Mar. 31, 2026

It’s very obvious to this USC diehard fan, Lincoln Riley is not delivering on his commitment to restore Trojans football to national prominence as head coach.

From Los Angeles Times • Jan. 3, 2026

The Athletic added in a Friday report that the two negotiators “remain far apart” on their respective demands, frustrating the YouTube TV viewers who make up “some of the most diehard NFL fans anywhere.”

From Slate • Nov. 10, 2025

This is a product for a Springsteen diehard, and not someone who just discovered this whole story thanks to the film and would like to learn more.

From Salon • Oct. 28, 2025

It’s as if they’re a group of diehard Yankees fans at a baseball game.

From "The Tipping Point" by Malcolm Gladwell