Diehard and Standpat

Diehard noun - One who adheres to traditional views.

Standpat and diehard are semantically related in overenthusiastic person topic. In some cases you can use "Standpat" instead the word "Diehard" as a noun or an adjective.

Standpat adjective - Tending to favor established ideas, conditions, or institutions.

Diehard and standpat are semantically related in moderate topic. You can use "Diehard" instead the word "Standpat" as a noun or an adjective, if it concerns topics such as conservative.