a person who shows zeal.

an excessively zealous person; fanatic.

( initial capital letter ) a member of a radical, warlike, ardently patriotic group of Jews in Judea, particularly prominent from a.d. 69 to 81, advocating the violent overthrow of Roman rule and vigorously resisting the efforts of the Romans and their supporters to heathenize the Jews.

noun

moderate

noun

activist , diehard , extremist , fanatic , fiend , maniac , militant , nut , radical , ultra * , young turk , enthusiast , sectary , votary , bug , devotee , revolutionary , revolutionist , ultra , partisan