noun
zealot
ZEL-ut/ˈzelət/
A person devoted to a cause in an extreme or uncompromising way.
The zealot shouts from a stool, ignoring every calm objection.

Etymology
Greek zēlōtēs meant a zealous follower. In English, the name first designated members of a militant Jewish sect resisting Roman rule, then broadened into the usually disparaging label for a fanatical enthusiast.
In context
she didn't drink at all while she was in office and she worked fiercely and was viewed as a zealot to enforce the law
More examples
- The diet zealot refused to consider evidence against her strict rules.
- The party's zealots treated every compromise as a betrayal.
- You can defend your beliefs without becoming a zealot.
Forms
zealot · zealots
zeal noun — strong enthusiasm for a cause or goal
Similar words
- fanatic
- Can describe extreme enthusiasm for sports as well as causes.
- adherent
- Indicates support without implying unreasonable devotion or intolerance.
- evangelist
- Emphasizes persuading others to join, not refusing opposing views.