true believer

American  

noun

1. a person who has been thoroughly convinced of something.

2. a fanatic, especially a religious or political one.

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Example Sentences

Residents Assn. is as die-hard a true believer as Bastian, and she went on for several minutes about music venues, farmers markets, dining, diversity and the sense of community.

From Los Angeles Times

Some artists her age don’t care much about the album format but Spiro is a true believer.

From Los Angeles Times

Whether or not Altman is a true believer in A.I.’s equalizing powers, he’s talking his book.

From Slate

Eliasch added: "Trust me, I am a true believer in also prioritising the sport for the athlete. And here we need to be clever so that in some cases we are a bit skewed."

From Barron's

He gave me an opportunity, plus many other people over the years, and he's a true believer in diversity, not someone that just says it.

From BBC