This is the 1554th most frequent Japanese word.
信者
Believer; follower; adherent.
In this sentence, 信者 (しんじゃ) refers to a person who believes in a specific religion or doctrine.
彼は熱心な宗教の信者です。
He is a devoted religious follower.
Here, 信者 denotes individuals who accept and follow a particular ideology or philosophy.
その哲学の信者は多いです。
There are many adherents to that philosophy.
信者 is used metaphorically to describe loyal followers or enthusiasts of a musical band.