IPA: /ˈzɛlət/
KK: /ˈzɛlət/
A person who is extremely passionate and dedicated to a cause, often to the point of being fanatical.
The zealot refused to listen to any opinions that contradicted his beliefs.
Zealot comes from the Greek word 'zelotes' (meaning one who is zealous or fervent) and the suffix '-ot' (used to form nouns). The term originally referred to a member of a Jewish sect in the first century that was zealous for the law and the temple, thus describing someone who is fervently devoted to a cause.
Think of someone who is 'fervently devoted' ('zelotes') to a cause, which is why a zealot is someone who shows great enthusiasm or passion.
No commonly confused words.