The nationalistic Jewish partisans of the first century a.d., particularly those active in the Jewish War (66-70). The word “zealot” is Greek zelotes, and in the NT and the writings of Josephus represents the Hebrew qanna' or its Aramaic equivalent qan'ana; one of Jesus' disciples was a “zealot” or “Cananaean” (cf. Mark 3:18; Luke 6:15 RSV). The term could signify a religious enthusiast in general, then a militant nationalist, and finally a member of the religio- political party, the “fourth philosophy” (Josephus) of first- century Judaism,* which took a prominent part in the struggle against Rome.
The chief spiritual antecedents of the Zealot movement were the Maccabees, whose ardent religious zeal inspired them to take up the sword and wage a victorious campaign against their pagan Greek overlords in the second century b.c. The Maccabean ideal was not forgotten, and it revived after the Roman conquest of Palestine. The Zealot party as such was probably formed, or had its immediate origins, in the abortine revolt caused by the Roman census of a.d. 6; its first leader was Judas the Galilean (Acts 5:37), whose sons carried on the movement after his death. The last stand of the Zealots was at the fortress of Masada, captured by the Romans in a.d. 73.
W.R. Farmer, Maccabees, Zealots and Josephus (1956); M. Simon, Jewish sects at the time of Jesus (ET 1967); F.F. Bruce,History (1969), pp. 88-95.
International Standard Bible Encyclopedia (1915)
zel’-ut, zel’-uts: Simon, one of the apostles, was called "the Zealot" Zelotes from zeloo "to rival," "emulate," "be jealous," "admire," "desire greatly,"
See, further, SIMON THE ZEALOT.