noun
advocate; propagator
Refers to a person who actively promotes or spreads an idea, doctrine, or cause. Somewhat formal and often used in political, ideological, or religious contexts.
彼は自由貿易の鼓吹者として知られている。
He is known as an advocate of free trade.
その宗教の鼓吹者たちは各地で布教活動を行った。
The propagators of that religion carried out missionary work in various places.
宣伝者 emphasizes publicity or propaganda, whereas 鼓吹者 focuses on advocacy and propagation of beliefs or doctrines.
Compound of 鼓吹 (kosui, 'advocacy' or 'propagation') and 者 (sha, 'person'). 鼓吹 originally meant 'to blow a flute and beat a drum', metaphorically extended to 'promote' or 'advocate'.