listen to the pronunciation of diehard
Englisch - Türkisch
Englisch - Englisch
fanatically opposing progress or reform
unreasonably or stubbornly resisting change
a person with such an attitude
complete; having no opposite opinion of anything in a particular topic of one's values; thorough of in one's beliefs

For a Roman Catholic teacher, he sure is a diehard fundamentalist.

A diehard is someone who is very strongly opposed to change and new ideas, or who is a very strong supporter of a person or idea. someone who opposes change and refuses to accept new ideas
{i} one who is stubborn or headstrong; one who is conservative
one who adheres to traditional views
plural of diehard